CHEMICAL  PROBLEMS. 


STAMMER. 


Richter's  Chemistry. 

A  Standard  and  Popular  Text-Book. 


VOL.  I. — INORGANIC  CHEMISTRY.    From  the  Fourth  German  Edition.    89 

Wood-cuts  and  Colored  Lithograph  of  Spectra. 
VOL.  II. — THE    CHEMISTRY  OF  CARBON    COMPOUNDS,  or,  ORGANIC 

CHEMISTRY.     From  the  Fourth  German  Edition.     Illustrated. 

Authorized  Translations  by 

EDGAR  F.  SMITH,  M.A.,  Ph.D., 

Prof,  of  Chemistry  in  Wittenberg  College,  Springfield,  Ohio ;  formerly  in  the 
Laboratories  of  the  University  of  Pennsylvania  and  Muhlenberg  Col- 
lege ;   Member  of  the  Chemical  Societies  of  Berlin  and 
Paris }  of  the  Academy  of  Natural  Sciences 
of  Philadelphia,  etc.,  etc. 

In  most  of  the  chemical  text-books  of  the  present  day,  one  of  the 
striking  features  and  difficulties  with  which  teachers  have  to  contend  is 
the  separate  presentation  of  the  theories  and  facts  of  the  science.  These 
are  usually  taught  apart,  as  if  entirely  independent  of  each  other.  In  this 
work,  which  has  been  received  with  such  hearty  welcome,  theory  and  fact 
are  brought  close  together,  and  their  intimate  relation  clearly  shown. 
From  careful  observation  of  experiments  and  their  results,  the  student  is 
led  to  a  correct  understanding  of  the  interesting  principles  of  chemistry. 
The  matter  is  so  arranged  as  to  adapt  the  work  to  the  use  of  the  beginner, 
as  well  as  for  the  more  advanced  student  of  chemical  science. 

From  F.  A.  GENTH,  Prof,  of  Chemistry,   F.  A.  GENTH,  JR.,  Ass't  Prof,  of  Chemistry, 

University  of  Pennsylvania. 

"  We  have  examined  with  much  care  the  '  Inorganic  Chemistry  '  of  Prof.  Victor  von 
Richter,  recently  translated  by  Dr.  E.  F.  Smith.  Both  theoretical  and  general  chemis- 
try are  treated  in  such  a  clear  and  comprehensive  manner  that  it  has  become  one  of  the 
leading  text-books  for  a  University  course  in  Germany.  We  are  indebted  to  Dr.  Smith 
for  his  translation  of  this  excellent  work,  which  may  help  to  facilitate  the  study  of 
chemistry  in  this  country." 

This  work  is  now  recommended  at  Dartmouth  College,  Hanover,  N.  H.; 
Rensselaer  Polytechnic  Institute,  Troy,  N. Y. ;  Wittenberg  College,  Spring- 
field, Ohio;  University  of  Pennsylvania,  Philadelphia;  Muhlenberg  Col- 
lege, Allentown,  Pa. ;  West  Virginia  State  University,  Morgantown ; 
Swarthmore  College,  near  Philadelphia;  Wisconsin  State  University, 
Madison ;  Trinity  College,  Hartford,  Conn.,  and  many  other  Schools  and 
Colleges. 

*V*  Correspondence  is  invited  from  teachers  and  professors  of  chemistry 
in  reference  to  the  introduction  of  these  books.  Each  volume  sold  sepa- 
rately. 

P.  BLAKISTON,  SON  &  CO., 
Medical    Publishers    and     Booksellers, 

1012  "WALNUT  STREET,  PHILADELPHIA. 


CHEMICAL  PROBLEMS. 


BY 


DR.  KARL  STAMMER- 


TRANSLATED  FROM  THE  SECOND  GERMAN    EDITION, 
WITH    EXPLANATIONS  AND  ANSWERS, 


BY 


W.  S.    HOSKINSON,  A.M., 

WITTENBERG  COLLEGE,  SPRINGFIELD,  O. 


i «   •    • 


PHILADELPHIA : 

P.   BLAKISTON,   SON    &    CO., 

No.  1012  WALNUT  STREET. 
1885. 


Entered  according  to  Act  of  Congress,  in  the  year  1885,  by 

P.  BLAKISTON,  SON  &  CO., 
In  the  Office  of  the  Librarian  of  Congress,  at  Washington,  D.  C. 


PRESS  OF  WM.  F.  FELL  &  CO., 

1220-24  SANSOM  STREET, 

PHILADELPHIA. 


CONTENTS. 


PART    FIRST. 

PAGE 

I.  OXYGEN 9 

II.  HYDROGEN 13 

III.  CHLORINE 16 

IV.  NITROGEN 19 

V.  SULPHUR 23 

VI.  PHOSPHORUS 28 

VII.  CARBON 29 

VIII.  FLUORINE 33 

IX.  POTASSIUM 34 

X.  SODIUM 37 

XI.  AMMONIUM 40 

XII.  BARIUM 4  41 

XIII.  CALCIUM 42 

XIV.  MAGNESIUM 44 

XV.  ALUMINIUM , 45 

XVI.  IRON 45 

XVII.  MANGANESE 48 

XVIII.  CHROMIUM 49 

XIX.  ZINC 50 

XX.  COPPER. 51 


237336 


VI  CONTENTS. 

PAGE 

XXI.  MERCURY 54 

XXII.  LEAD 56 

XXIII.  SILVER 57 

XXIV.  TIN 59 

XXV.  ANTIMONY 60 

XXVI.  ARSENIC 61 

XXVII.  PLATINUM...  62 


PART    SECOND. 

XXVIII.    APPROXIMATE  RATIOS 63 

XXIX.    TEMPERATURE  AND  ATMOSPHERIC  PRESSURE 64 

XXX.     MIXED  PROBLEMS ." 65 

ANSWERS  TO  PROBLEMS 83 


ATOMIC  WEIGHTS. 


Aluminium Al  27.4 

Antimony Sb  122 

Arsenic As  75 

Barium Ba  137 

Bismuth Bi  208 

Boron B  II 

Bromine Br  80 

Cadmium Cd  112 

Calcium Ca  40 

Chlorine Cl  35.5 

Chromium Cr  52 

Copper Cu  63.4 

Carbon C  12 

Fluorine Fl  19 

Gold Au  197 

Hydrogen H  I 

Iron Fe  56 


Iodine I  127 

Lead Pb  207 

Magnesium Mg  24 

Manganese..* Mn  55 

Mercury Hg  200 

Nitrogen. N  14 

Oxygen O  16 

Phosphorus P  31 

Platinum Pt  198 

Potassium K  39 

Sulphur S  32 

Silver Ag  108 

Silicon Si  28 

Strontium Sr  88 

Sodium Na  23 

Tin Sn  118 

Zinc Zn  65 


Vlll 


CHEMICAL  PROBLEMS, 


PART    FIRST. 


I.— OXYGEN. 

1.  How   much   oxygen    can   be   obtained   by   heating 

216  g  mercuric  oxide? 

2.  How   much    oxygen    can   be    obtained   by   heating 

mercuric  oxide  as  follows  : — 

a.  108  g,  c.  5.4  Kg,  e.  1.08  g? 

b.  54  g,  d.  i  Kg  80  g, 

Solution  :  216  parts  oxide  produce  16  parts  oxygen. 
108  g  produce  the  half,  or  8  g,  etc. 

3.  How  much  oxygen  can  be  obtained  by  heat  from 

20  g  mercuric  oxide  ? 

Solution:  216  parts  oxide  give  16  parts  oxygen. 

i  part       "      gives  ^T6^  "         " 
20  g  "      give  20  X  i&  =  148  g. 

Orthus:2?i6(-    etc. 

4.  How  much  oxygen  is  obtained  from  i  Kg  mercuric 

oxide  ? 

5.  How  much  oxygen  will  be  obtained  from — 

«•  67%  &  b.  675  g,  c.  337.5  g? 

6.  What  amount  of  oxygen  can  be  obtained  by  heat 

from  potassium  chlorate,  as  follows  : — 

a.  245  g,  c.  367.5  g,  e.  0.245  Kg? 

b.  122.5  g>  d.  2.45  g, 

Solution:  K2O,  C12O5  =  2  KC1  +  6  O. 
(KC103  =  KC1  +  3  O.) 
K2  78) 

C12  71  \  245  parts  furnish  96  parts  oxygen,  etc. 
06  96  J 

(Or:   122.5  parts  furnish  48,  etc. 
B  9 


10 


PROBLEMS. 


7.  By  this   operation  how  much  mercury  is  left  from 

I  to  5  ? 

8.  How  much  potassium  chloride  is  obtained  by  6  ? 

9.  How  much  oxygen  is  obtained  by  heat  from   10  g 

potassium  chlorate? 

Solution  :  One  molecule  by  weight,  or  245  parts,  give  6  combined 
weight  or  96  parts.  (Or:  122.5  Parts  give  48,  etc.) 
I  part  by  weight  gives  also  ^  parts;  and  10  g  —  --9-6  g. 
Or  :  How  many  give  log,  when  245  g  give  96  g  ? 


10.  What  per  cent  of  oxygen  is  obtained  from  a  given 

weight  of  potassium  chlorate  ? 

11.  How  much  oxygen  is  contained  in,  a.  \  Kg,  b.  2^ 

Kg  of  potassium  chlorate  ? 

12.  How    much    oxygen    is    obtained    from    potassium 

chlorate  as  follows  :  — 

a.  2.5521  g,  b.  81.8  g,  c.   i  g? 

13.  How   much   potassium    chloride    remains    in   these 

cases  ? 

14.  How  many  grams  and  kilograms  of  oxygen  are  con- 
tained in  black  oxide  of  manganese  as  follows  :  — 

a.  87  g,  c.  870  g,  e.  217.5  g? 

b.  8.7  Kg,  d.  21.75  Kg, 

15.  How  many  flbs.  of  oxygen  are  contained  in,  a.  100 

Kg,  b.  i  Bb.  black  oxide  of  manganese  ? 
1  6.  How  much   of  the  oxygen    contained    in    87   g   of 

black   oxide  of  manganese  will  be  set  free  by  sul- 

phuric acid  ? 
17.  a.  What  quantity  of  the  oxygen  contained  in  100  Kg 

of  manganese  di-oxide  will  be  obtained  by  heating 

the  same  with   sulphuric   acid  ?     b.  How  much  of 

that  contained  in  one  ft)  ? 
1  8.  How  many  kilograms  of  oxygen  are  obtained,  by 

means  of  sulphuric  acid,  from  manganese  di-oxide, 

as  follows  :  — 

a.   i  cwt,  b.   10  Kg,  c.  29  g? 


CHEMICAL    PROBLEMS.  11 

19.  a.  How  much  oxygen  can  be  obtained  by  heating 

261  g  of  black  oxide  of  manganese? 

Solution:  3  Mn  O2  =  Mn3  O6  =  Mn3  O4  -f-  2  O. 

Or:  261  parts  by  weight  give  32  parts  by  weight. 

How  much  from, — 

b.  130.5  g,  d.  26.1  Kg, 

c.  1.305  g,  e.  32.6  g,  /  522  Kg? 

20.  How   much    is    obtained   by   heating   the   specified 

quantities  in  examples  16,  17,  18? 

21.  What  per  cent,  of  the  oxygen  contained   in  black 

oxide  of  manganese    is    obtained,   a.  by  sulphuric 
acid;  b.  by  heat?     c.  What  per  cent,  more  by  first? 

22.  If  the  quantity  of  oxygen  be  given  which  is  con- 

tained in  a  given  quantity  of  manganese,  how  does 
one  find  that  which  is  actually  set  free  ? 

23.  How  much  sulphuric  acid   is    needed    in    order   to 

decompose  87  g  of  black  oxide  of  manganese  ? 

24.  How  much    oxygen  and   manganous    sulphate    are 

obtained  ? 

25.  How  much  sulphuric  acid  is  needed  to  decompose 
the  following  quantities  of  manganese  di-oxide : — 

a.  43.5  Kg,  c.  i  cwt, 

b.  6.2  g,  d.  10  Ebs.  ? 

26.  How   much    manganous    sulphate    is    obtained    by 

25  a  to  d? 

27.  How   much    mercuric    oxide    is    required    to    yield 

oxygen  as  follows  : — 

a.  1 6  g,  c.  24  g,  e.  4g? 

b.  32  g,  d.  8  g, 

28.  How  much    mercuric   oxide   is    necessary  to   yield 

the  following  amounts  of  oxygen  : — 

a-  l  Kg,  c.  5  g,  e.  1.4336  g? 

b.  2  g,  d.   10  g, 

29.  How  would  you  find  simply  the  necessary  quantity 

of  mercuric  oxide  for  a  given  quantity  of  oxygen  ? 


12  CHEMICAL   PROBLEMS. 

30.  How  much  potassium  chlorate  is  necessary  to  obtain 

oxygen  as  follows  : — 

a.  96  g,  c.   144  Kg,  e.  96  g? 

b.  48  g,  d.  0.96  g, 

31.  How  much  potassium  chlorate  is  necessary  to  yield 

oxygen  as  follows  : — 

a.  i  g,  c.  3.919  g,  e.   1.4336  g? 

b.  i  Kg,  d.  0.3919  g, 

32.  How  much  manganese  di-oxide  is  needed  to  yield, 
by  heat,  16  Kg  of  oxygen  ? 

Solution:  3  MnO2  or  216  parts  by  weight  give  2  O  or  32  parts  by 
weight.  Thus,  32  Kg  are  obtained  from  216  Kg;  or, 
1 6  Kg  from  130.5  Kg. 

33.  How  much  manganese  di-oxide  is  required  to  yield, 

by  heat,  oxygen  as  follows  : — 

*•  4g,  &  0-l6g,  c.  3.2  Kg? 

34.  How  much  to  yield — 

a.  10.6667  Kg,        c.  0.1226  g,  e.  1.226  Kg, 

b.  12.26  Kg,  d.  6.13  Kg,  /.  3.55  g? 

35.  How  much  manganese  di-oxide  is  needed  to  yield 

oxygen  by  means  of  sulphuric  acid,  as  follows : — 
a.  1 6  g,         £.8  g,         c.  4  Kg,         d.  0.4  Bbs.  ? 

36.  How  much  by  the  same  for — 

a.  9.2  Kg,  c.  5.33  g,  e.  o.i84g, 

b.  1.84  Kg,  d.  18.4  g,  /.   100  g? 

37.  How  much  sulphuric  acid  is  used  in  all  these  cases  ? 

38.  How  much  manganese  di-oxide  and  sulphuric  acid 

are  needed  to  yield  oxygen  as  follows : — 

a.  16  g,  c.  100  g,  e.   1.4336  g? 

b.  20  &s.,  d.   i  Kg, 

Solution :  It  is  necessary,  in  the  first  place,  to  reckon  the  quantity 
of  manganese  di-oxide,  and  then  the  necessary  quantity 
of  oxygen  for  the  decomposition  of  the  same. 

The  following  problems,  relating  to  definite  volume 
ratios,  are  most  practicably  considered  after  solving 
those  under  II. 


CHEMICAL   PROBLEMS.  13 

39.  How  much    mercuric   oxide    is    necessary  to   yield 

i  cu  dm  of  oxygen  ? 

40.  How  much    mercuric   oxide   is    necessary  to   yield 

1.5  cu  m  of  oxygen? 

41.  How  many  cubic  meters  of  oxygen  will  the  follow- 

ing quantities  of  potassium  chlorate  furnish  : — 
a.  i  cwt,  b.  10  Kg,  c.  3.659  g? 

42.  How  much  manganese  di-oxide  and  sulphuric  acid 

are  necessary  to  give  i  cu  dm  of  oxygen  ? 


II.— HYDROGEN. 

1.  How  much  a.  hydrogen,   b.  oxygen,   are  contained 

in  1 8  Kg  of  water  ? 

2.  How  much  hydrogen  and  oxygen  are  contained  by 

weight  in  water  as  follows  : — 

a.  9  Kg,  d.  9000  g,  g.  1 8  cu  cm, 

b.  36  g,  e.  81  Kg,  h.  91? 

c.  27  g,  /.  0.18  g, 

3.  How  much   hydrogen   and   oxygen  by  weight  can 
be  obtained  from  water,  by  the  use  of  the  galvanic 
current,  as  follows  : — 

a.  i  Kg,  c.  1000  cu  cm, 

b.  50  g,  d.  0.25  1? 

4.  How  much  hydrogen  is   obtained,  by  passing  the 
vapor  from  water  over  iron,  as  follows : — 

a.  1 8  g,  c.  o.i  Kg,  e.  300  cu  cm, 

b.  30  g,  d.  10  cu  cm,          /.  i  1? 

5.  About  how  much  heavier  will  the  tube  with  the  iron 

be  at  this  time  ? 

6.  What  is  the  percentage  composition  of  water  ? 

7.  How,  in  general,  do  we  ascertain  the  quantity  of 

hydrogen  set  free  from  a  given  quantity  of  water  by 


14  CHEMICAL   PROBLEMS. 

any  method,  and  also  the  quantity  of  oxygen  that 
at  the  same  time  enters  combination  ? 

8.  How  much  hydrogen  is  obtained  by  the  use  of  98  g 
of  sulphuric  acid  and  65.2  g  of  zinc? 

9.  How  much  hydrogen  is  obtained  from — 

a.  49  Kg  of  sulphuric  acid  and  32.6  Kg  of  zinc, 

b.  100  g  "  "     66.5  g         "         ? 

10.  Is  it  necessary  that  the  quantities  of  both  substances 
be  given,  or  is  the  quantity  of  one  of  them  depend- 
ent upon  the  other  ?     What  occurs  if,  for  example, 
100  g  of  zinc  act  upon  100  g  of  sulphuric  acid? 

11.  How  much  hydrogen  can  be  obtained  by  means  of 

7  Kg  of  sulphuric  acid  applied  to  zinc  or  iron  ? 

12.  How  much  hydrogen  does  a  sufficient  quantity  of 
water  and  zinc  give  when  12.74  g  of  sulphuric  acid 
are  used  ? 

13.  How  much  hydrogen  can  be  obtained  by  the  use  of 

zinc  without  water,  and  sulphuric  acid  as  follows : — 

a.  179.3  g,  c.  217.116  Kg, 

b.  299.2  g,  d.  26.08  Kg? 

14.  How  many  liters   of  hydrogen   will   the   following 

amounts  of  water  furnish  : — 

a.  0.8064  g,  b.  80.64  g,  c.   I  Kg? 

15.  How  many  liters  of  oxy-hydrogen  gas  will    i  1    of 

water  give  ? 

1 6.  How  many  liters  of  explosive  gas  will   I  cu  cm  of 
water  furnish  ? 

17.  How  many  cubic  centimeters  of  oxy-hydrogen  gas 

will  yield  1000  cu  cm  of  steam  at  o°  and  760  mm 
pressure  ?  How  is  the  former  volume  related  to 
the  latter? 

1 8.  How  much  sulphuric  acid   is   necessary  to  liberate 

the  hydrogen  from  18  Kg  of  water?  How  much 
zinc? 

19.  What  amounts  of  sulphuric  acid  and  zinc  are  required 

for  the  decomposition  of  1 5  g  of  water  ? 


CHEMICAL   PROBLEMS.  15 

Solution:    Zn  +  H2O  -f  SO3,H2O  ==  ZnO,SOs  +  H2O  -f  2H 

65.2         18  98  161.2  18  2 

(Or,  Zn  +  H20  -f  H2SO4  ==  ZnSO4  +  H2O  +  2H.) 

For  1 8  parts  by  weight  it  is  necessary  to  have  98  of 
sulphuric  acid  to  65.2  Zn. 

For  i  part      --  of  sulphuric  acid  and  -~  zinc. 

For  15  parts  9 — -—  sulphuric  acid  and  — '  zinc,  etc. 

Or  thus  :;g  |  15  etc.  18\  %.,«*• 

20.  How  much  sulphuric  acid  and  zinc  are  needed  for 
the  given  quantities  of  water  in  No.  14  above? 

21.  How  much   lighter  must  the  weight  of  the  retort 

become,  which  holds  the  water  whose  vapor,  by 
coming  in  contact  with  heated  iron,  yields  hydrogen 
as  follows : — 

a.  3  g,  c.  4.5  g,  e.  8.96  g? 

b.  90  g,  d.   10  g, 

22.  About   how  much   heavier   will   the   tube   become 

thereby  ? 

23.  What  amount   of  sulphuric  acid  and   zinc  are  re- 

quired to  yield  hydrogen  as  follows : — 

a.  2  Kg,  c.  0.0896  g, 

b.  100  g,  d.  89.6  g? 

24.  How  much   water   must   be    decomposed   to   yield 

hydrogen  as  follows  : — 

a.  1000  cu  cm,  c.  1000  HI  (Ans.  in  Kilos)  ? 

b.  100  1  (Ans.  in  liters), 

25.  What  amount  of  sulphuric  acid  and  zinc  is  necessary 

to  obtain  the  same  quantities  ?     (Ans.  in  g  and  K). 


16  CHEMICAL   PROBLEMS. 

III.— CHLORINE. 

1.  How  much  chlorine  can  be  obtained  from  the  follow- 

ing amounts  of  hydrochloric  acid  (gas)  by  means 
of  manganese  di-oxide  : — 

a.   146  Kg,  b.   146  Sbs.,  c.   1.46  g? 

2.  What  quantity  of  chlorine  is  evolved  by  the  union 

of  the  following  amounts  of  muriatic  acid  and  an 
indefinite  amount  of  manganese  di-oxide  : — 

a.  73  g,  b.  7  Kg  300  g,       c.  7.3  g? 

3.  How  much  Cl  are,  a.  87  g,  b.  0.87  Kg,  c.   100  Sbs., 

d.  20  g,  of  black  oxide  of  Mn.  able  to  liberate 
from  HC1? 

4.  How   many   cubic   decimeters    of  chlorine    can   be 

obtained   from,   a.    100  g   of  manganese   di-oxide; 

b.  100  g  of  muriatic  acid  ? 

5.  How  much  muriatic  acid  is  required  for  manganese 

di-oxide  as  follows  : — 

a.  87  ft)s.,  c.   100  g, 

b-  43-5  g,  d.   i  Kg? 

6.  What  amount  of  manganese  di-oxide  must  be  taken 

with  the  following  quantities  of  hydrochloric  acid  to 
yield  chlorine,  if  all  of  both  substances  be  decom- 
posed : — 

a.  146  g,  d.   10  Sbs., 

b.  I  Kg  460  g,  e.   16.78  g, 

c.  I  Bb.,  /.   1678.17  g? 

7.  How  much  black  oxide  of  manganese  and  muriatic 

acid  are  necessary  to  yield  chlorine  as  follows : — 

a.  71  g,  d.  40.804  Kg, 

b.  35.5  fts.,  e.  81.61  g, 

c.  7-1  g,  /  48-63  g? 

8.  What  amounts  of  manganese  di-oxide  and  hydro- 

chloric acid  are  needed  to  make  chlorine  as  follows : — 
a.  128.30  cu  dm,  b.  152.9  cu  dm,  c.  I  cu  m  ? 


CHEMICAL   PROBLEMS.  17 

9.   How  much  sulphuric  acid,  common  salt,  and  manga- 
nese di-oxide  are  necessary  to   give  the  following 
amounts  of  chlorine  : — 
a,  71  g,  b.  7.1  ft>s.,  c.   100  g? 

Solution:    MnO2   +  2  (SO3,H2O)  -+-  2  NaCl  == 

87  196  117.0 

MnO,SO3  -f  Na2O,SO3  -f  2  Cl  -f  2  H2O. 

7i 

(MnO2  -f  2  (H2SO4)  +  2  NaCl  = 
MnS04  +  Na2S04  +  2  Cl  f  2  H2O.) 

10.  How  much  sulphuric  acid,  common  salt,  and  manga- 

nese di-oxide  must  be  taken  to  give  the  following 
amounts  of  chlorine  : — 

a.  100  1,  b.  I  cu  m  ? 

1 1.  How  many  grams  of  chlorine  will  be  absorbed  by  10  1 

of  water,  if  the  water  takes  up  twice  its  volume  ? 

12.  In  what  proportion  will  the  water  become  heavier  if 

it  takes  up  twice  its  volume  of  chlorine  ? 

13.  How  many  cubic  centimeters   of  chlorine  are  con- 

tained in   100  g  of  chlorine  water,  if  one  volume  of 
water  has  absorbed  two  volumes  of  chlorine  ? 


HYDROCHLORIC   ACID. 

14.  How  much  hydrochloric  acid  gas  is  obtained  from 

common  salt  as  follows  : — 

a.  117  fbs.,  d.  100  fibs., 

b.  58.5  Kg,  e.  1000  g, 
.  c.  11.7  g,  /   I  g? 

15.  How  much  hydrochloric  acid  gas  may  be  obtained 

from  an  indefinite  quantity  of  common  salt  by  means 
of  sulphuric  acid  as  follows  : — 

a.  98  fibs.,  d.   I  g, 

b-  49  g.  e>  25°  g> 

c.  4.9  g,  /.  100  Kg? 


18  CHEMICAL   PROBLEMS. 

1 6.  How   much   sulphate   of  soda   remains   behind   in 
these  cases? 

17.  What  amount  of  common  salt  is  necessary  to  obtain 

all  the  chlorine  in  the  shape  of  hydrochloric  acid  gas 
by  means  of  sulphuric  acid  as  follows : — 

a.  98  g,  d.   no  Ebs., 

b.  49  fcs.,  e.   1000  g, 

c-  0.7  g,  /•  25  g? 

1 8.  What  quantity  of  sulphuric  acid  and  common  salt 

must  be  taken  to  yield  the  following  amounts  of 
hydrochloric  acid  gas  : — 

a.  73  fts.,  c.   I  Kg, 

b.  36.5  g,  d.  100  g? 

19.  By  their  union,  one  volume  of  hydrogen  and   one 

volume  of  chlorine  yield  2  volumes  of  hydrochloric 
acid  gas.  What,  therefore,  is  the  volume  by  weight 
of  the  latter  referred  to  hydrogen  as  unit  ?  How 
much  is  contained  in  the  liter  ? 

20.  How  much  sulphuric  acid  and  common  salt  are  neces- 

sary to  yield  I  cu  m  of  hydrochloric  acid  gas  ? 

21.  What  amount  of  sulphuric  acid  and  common  salt 

must  be  mixed,  and  how  much  water  is  used,  to 
obtain  the  following  amounts  of  aqueous  gas,  30  per 
cent,  of  the  contents  of  which  is  pure  acid : — 
a.  233^  Ibs.,  b.  4666.667  g,         c.  700  Kg? 

How  much  sodium  sulphate  is  produced  ? 

Solution :  First  reckon  how  much  anhydrous  hydrochloric  acid  gas 
is  wanted;  from  this  find  the  individual  substances. 

22.  What  per  cent,  of  its  weight  of  hydrochloric  acid 

gas  does  water  contain,  which  has  absorbed  400 
times  its  volume  of  this  gas  ? 

23.  What  per  cent  of  hydrochloric  acid  gas  does  the 

liquid  contain,  when  one  liter  of  water  has  absorbed 
50  1  of  the  gas  ? 

24.  How  many  cubic  centimeters  of  hydrochloric  acid 

gas  does  I  g  of  aqueous  acid  contain  which  corre- 
sponds to  the  formula  HC1  +  5  H2O  ? 


CHEMICAL   PROBLEMS.  19 

IV.— NITROGEN. 

1.  If  the  spec.  grav.  by  weight  of  air  amounts  to  ^  in 

relation  to  water,  how  great  is  the  same  in  relation 
to  hydrogen  ? 

2.  What  does  I  cu  m  of  air  weigh  at  o°  and  760  mm 

pressure  ? 

3.  How  much  is  the  spec.  grav.  by  weight  of  air  in 

relation  to  water;  how  much  is  that  of  water  in 
relation. to  air  as  unit? 

4.  What  is  the  volume-weight  of  air  referred  to  oxygen 

as  unit  ?     What,  referred  to  nitrogen  as  unit  ? 

5.  If  it  be  granted  that  air  consists  of  79  volumes  of 

nitrogen  and  21  oxygen,  how  many  times  heavier 
is  one  volume  of  air  than  an  equal  volume  of 
hydrogen  ? 

6.  Compute  from  the  data  in  the  preceding  examples 
the   percentage   composition   of  air.     (Spec.  grav. 
of  nitrogen  =  14.) 

7.  Required  I  cu  m  of  nitrogen.     How  much  air  is  to 
be  deprived  of  oxygen,  and  how  much  phosphorus 
must  be  burned  (composition  of  air  as  in  Ex.  5), 
if  62  parts  of  phosphorus  unite  with  80  parts  of 
oxygen  ? 

NITRIC   ACID. 

8.  How  much   nitric  acid  is   obtained  from    170  g  of 

sodium  nitrate  ? 
Solution:  Na2O,N2O5  -f  SO3,H2O  =  Na2O,SO3  +  N2O5,H2O. 

170  98  142  126 

[2  (Na,NO3)  4-  H2SO4  =  Na2SO4  +  2  (HNO3)  ]. 

9.  How  much  nitric  acid  (N2O5,H2O)  is  obtained  from 
the  following  amounts  of  sodium  nitrate : — 

a.  85  Bbs.,  d.  8.517  g, 

b.  17  g,  e.   i  Kg  700  g, 

c.  i  Kg,  /.  8.5  g? 

10.  What  per  cent,  of  water  does  this  nitric  acid  con- 
tain? 


20  CHEMICAL    PROBLEMS. 

11.  How  much  anhydrous  acid  do  the  quantities  in  the 

foregoing  examples  contain  ? 

12.  How  much  water  must  be  taken  in  every  case  in 
order  that  the  acid  may  contain  40  per  cent,  water  ? 

13.  How  much   nitric  acid  containing  46  per  cent,  of 

its  amount  of  water  may  be  obtained  from  1700  g 
of  sodium  nitrate,  and  how  much  water  must  be 
taken  ? 

14.  What  amount  of  sulphuric  acid  is  needed  to  decom- 

pose the  following  quantities  of  sodium  nitrate : — 

a.  170  Kg,  c.  8.5  g,  e.  i  Kg, 

b.  85  fibs.,  d.  20  g,  /.   12  g? 

Solution:  Na2O,N2O5  +  SO3,H2O  =  etc. 

170  98 

(2  NaNO3  -f  H2SO4  =  etc. 
For  170  parts  98  are  needed. 
"        *  Part  T9yV      " 

20  X  08  ,       , 

"      20  parts are  needed,  etc. 

170 

15.  How  much  sodium  nitrate  and  sulphuric  acid  would 
be  required  to  yield  nitric  acid  as  follows : — 

a.  126  g,       c.  25.2  g,       e.  ico  g,       g.   i  Kg, 

b.  63  fibs.,     d.  6.3126  g,  f.  no  fibs.,    h.  700  g? 

1 6.  What  quantity  of  nitrate  of  soda  and  sulphuric  acid 

are  required,  and  how  much  water  must  be  taken  in 
order  to  obtain  the  following  amounts  of  acid  with 
40  per  cent,  of  the  water : — 

a.  450  fibs.,  b.  i  Kg  800  g  ? 

Solution :  First  reckon  the  quantity  of  anhydrous  acid  contained  in 
the  required  amount  of  acid,  then  the  amount  of  both 
substances  necessary  for  it,  and  from  the  water  belonging 
to  it  deduct  the  quantity  already  contained  in  it  as  hydrate.  " 

17.  How  much  nitric  oxide  may  be  obtained  from  the 

following  amounts  of  anhydrous  nitric  acid : — 

a.  432  fibs.,  c.   i  fib.,  e.  6  g? 

b.  216  g,  d.  2.84  g, 


CHEMICAL    PROBLEMS.  21 

Solution:  4  N2O5  -f  3  Cu  =  3  (CuO,N2O5)  -f  2  NO. 

432  60 

Or  =  3  [  (N03)  2Cu]  +  2  NO. 

1 8.  How  much  nitric  acid  may  be  obtained  from  the 

produced  nitric  oxide  by  mixing  with  air,  if  it  be 
granted  that  only  nitrous  acid  is  formed  ? 

19.  What  amount  of  nitric  oxide  and  nitrous  acid  (by 

the  same  conditions  as  18)  may  be  obtained  from 
the  following  quantities  of  nitric  acid  containing 
75  per  cent,  of  anhydrous  acid  : — 

a.  72  ft>s.,  b.  2  Kg,  c.  5  g  ? 

20.  About  how  much  heavier  will  any  quantity  of  water 

become  when  the  following  amounts  of  nitrous  acid 
have  passed  through  it : — 

a.  228  g,  b.  57  g,  c.  4g? 

AMMONIA. 

21.  What  is  the  percentage  composition  of  ammonia? 

22.  What  is  the  percentage  composition  of  sal-ammoniac? 

23.  How  much  does  one  liter  of  ammonia  gas  weigh  ? 

24.  What  is  the  spec.  grav.  of  ammonia  when  referred 

to  air  as  unit  ?     What,  referred  to  water  ? 

25.  How  many  grams  of  ammonia  gas  will  be  absorbed 
by  5  liters  of  water,  if  it  be  granted  that  it  takes  up 
500  times  its  volume  ?     In  what  proportion  will  the 
weight  of  the  water  be  increased  by  this  operation  ? 

26.  How  much  ammonia  will  the  following  quantities  of 

sal-ammoniac  furnish : — 

«•  53-5  g,      i>.  535  R>s.,        c.  i  ft.,         d.  icoog? 

27.  How  much  ammonia  may  be  obtained  from  56  g  of 
burnt  lime  and   107  g  of  sal-ammoniac?     Must  the 
quantities  of  both  materials  be  given,  or  is  one  con- 
ditioned by  the  other,  and  does  the  amount  of  lime 
given  suffice  for  the  calculation  of  the  ammonia  ? 


22  CHEMICAL   PROBLEMS. 

28.  What  amount  of  ammonia  can  be  made  from  the 

following  quantities  of  burnt  lime  by  means  of  sal- 
ammoniac  :  — 

a.  28  g,         b.  7  fts.,  c.  i  ft.,         d.   1000  g? 

29.  How  much  calcium  chloride  would  be  obtained  in 

these  cases  ? 

30.  How   much    burnt    lime    is    needed    to    yield    sal- 

ammoniac  as  follows  :  — 

a.   107  g,       b.  53.5  fts.,        c.  i  ft).,         d.  i  Kg? 

31.  How  much   sal-ammoniac   can   be   decomposed   by 

means  of  the  following  amounts  of  lime  :  — 

a.  56  g,  c.   i  Kg,  e.  5  23.36  g, 

b.  7  fts.,  d.  0.523  ft)s.,  /  57.57  g? 

32.  What   amount  of  sal-ammoniac   must   be    used    to 

yield  ammonia  as  follows  :  — 

a.  34  fts.,  c.  34.95  g,  e.  i  ft)., 

b.  17  g,  d.  317.757  g,          /  1000  g? 

Solution:  2  (NH4C1)  -f  ......  ===2  NH3  -f  .  .  .  . 

107  34 

For  34  take  107,  for  one  (i)  also  y^7  etc. 


33.  How  much  lime  must  be  used  to  yield  the  following 

amounts  of  ammonia  :  — 

a.  34  g,  c.  8.5  g,  e.  607.14  Jfes., 

b.  17  ibs.,  d.  0.60714  g,          /.   100  Sbs.  ? 

34.  How  much  sal-ammoniac  and  lime  are  necessary  to 

yield  ammonia  as  follows  :— 

a.   1000  g,  b.  10  fts.  ? 

35.  It  is  required  to  make  an  ammonia  solution,  in  which 

the  water  has  absorbed  700  times  its  volume  of 
ammonia  gas.  For  this  10  liters  of  water  are  taken. 
What  is  the  least  quantity  of  sal-ammoniac  and 
lime  necessary  ?  (Ans.  in  Kilos  ?) 


CHEMICAL    PROBLEMS.  23 

V.— SULPHUR. 

1.  How  much  sulphur  may  be  obtained  from  840  ft)s. 

of  iron  pyrites ;  how  much  burnt  residue  remains 
behind  ? 

2.  How  much   sulphur  and   residue   may  be  obtained 

from  the  following  quantities  of  pyrites: — 

a.  i  Kg,        b.  loco  ft>s.,       c.  35  g,  d.  i  ft).? 

3.  How  much  pyrites  is  necessary  to  obtain  the  follow- 

ing amounts  of  sulphur  by  distillation  : — 

a.  192  g,  c.   I  ft).,  e.  25z/7ft>s.? 

b.  96  g,  d>  8  KS> 

4.  What  amount  of  sulphurous  acid  (sulphur  di-oxide) 

results  from  the  decomposition  of  32  g  of  sulphur? 

5.  How   much   sulphurous  acid   may  be   obtained   by 

burning  the  following  amounts  of  sulphur : — 

a.   i  g,     b.  20  ft)s.,     c.  50  Kg,  .   d.   I  Kg,     e.  5  g? 

6.  What  is  the  spec.  grav.  of  sulphurous  acid  ?    (3  Vol. 

of  the  elements  give  2  Vol.  of  the  compound.)  How 
does  this  proportion  itself  to  the  spec.  grav.  of  sul- 
phur gas  and  oxygen  ? 

What  does  I  liter  of  sulphurous  acid  weigh  ?  How 
much  oxygen  is  contained  in  it? 

7.  How  many  liters  of  sulphurous  acid  are  formed  from 
the  following  amounts  of  sulphur : — 

a.  i  g,  b.  10  g? 

8.  How  much  sulphurous  oxide  may  be  obtained  by 
the"use  of  sulphuric  acid  and  the  following  amounts 
of  copper : — 

a.  63.4  g,   b.  6.34  fl>s.,    c.  i  Kg  585  g,    d.   1000  g? 

9.  What  amount  of  copper  sulphate  will  be  formed  in 

these  cases  ? 

10.  How  much   sulphurous   acid   will    result   from  the 

action  of  carbon  on  sulphuric  acid  as  follows  : — 

a.   196  g,  b.  98  ft)s.  ? 


24  CHEMICAL    PROBLEMS. 

11.  How  much  sulphurous  acid  may  be  obtained  from 
the  following  amounts  of  sulphuric  acid  by  means 
of  charcoal : — 

a.  196  fbs.,  c.  73.5  g, 

b.  100  flbs.,  d.  490  g  ? 

12.  How  much   carbonic  acid  will   be   formed    in  this 

reaction  ? 

13.  What  amount  of  sulphuric  acid  must  be  used,  if  it 

is  required  to  make   sulphurous  acid  by  the  con- 
sumption of  the  following  quantities  of  copper  : — 
a.  63.4  fts.,  b.  31.7  g? 

14.  How  much  sulphuric  acid  will  be  consumed  to  yield 

sulphurous  acid,  if  copper  be  consumed  as  follows : — 

a.  I  g,  c.   10.027  ft>s-> 

b.  5  g,  d.  1000  g? 

15.  How  much  copper  must  be  consumed  to  yield  sul- 
phurous acid  from  sulphuric  acid  as  follows : — 

a.  196  ft>s.,  d.  31  Sbs., 

b.  3.091  g,  e.  3  Kg  91.48  g? 
'•   1545  g> 

1 6.  How  much  charcoal  should  be  mixed  with  the  fol- 

lowing amounts  of  sulphuric  acid,  if  after  heating, 
charcoal  and  sulphuric  acid  disappear : — 

a.  196  g,  c.   i6j£  ft>s., 

b.  98  Ibs.,  d.   i  Kg  796.67  g? 

17.  By  the  consumption  of  6  g  of  copper  sulphurous 

acid  is  formed ;  a  solution  in  water  is  to  be  obtained 
in  which  the  same  has  absorbed  50  times  its  volume 
of  sulphurous  acid  gas ;  how  many  grams  of  water 
are  necessary  for  this  ? 

1 8.  How  much    carbon    di-oxide   is    formed   when  the 

following  amounts  of  sulphurous  acid  are  made 
from  charcoal  and  sulphuric  acid  : — 

a.  64  g,  c.2$  Ibs., 

b.  3  Kg  200  g,  d.  20  g  ? 


CHEMICAL    PROBLEMS.  25 

Solution  :    2  SO3  -f  C  ==  2  SO2  +  CO2. 

128  44 

From  every  128  parts  there  will  be  formed  44,  or  from 
every  32  there  will  be  II  parts  of  carbon  dioxide.  From 
I  part  also  ||,  etc. 


19.  How  much  (a)  sulphuric  acid,  (b)  sulphuric   oxide 

must  be  reduced  in  order  to  obtain  64  parts  by 
weight  of  sulphurous  acid  ?  How  much  oxygen 
must  the  sulphuric  acid  be  deprived  of? 

20.  How  much  sulphuric  acid  must  be  reduced  in  order 

to  obtain  the  following  amounts  of  sulphurous 
acid  :  — 

a.  32  ft)s.,  c.  5  Kg, 

b.  5  ft>s.,  d.  200  g  ? 

21.  What   portion    of  the   applied    sulphuric   acid   will 

be  reduced  (a)  by  the  use  of  copper,  (b)  charcoal  ? 

22.  How  much  sulphuric  acid  is   needed  to  yield  the 

following  amounts  of  sulphurous  acid  (i)  by  means 
of  copper,  (2)  by  means  of  charcoal  :  — 

a.  64  fibs.,  c.   10  fibs., 

b.  32  g,  d.  20  g? 

23.  How  much  sulphuric  acid  and  copper  are  needed  to 

yield  sulphurous  acid  as  follows  :  — 

a.   i  Kg,  b.   100  fibs.? 

24.  How  much  sulphuric  acid  and  charcoal  are  neces- 

sary for  the  same  quantities  ? 

25.  How  much  sulphuric  acid  and  charcoal  are  neces- 

sary to  yield  I  cu  m  sulphurous  acid  ? 

26.  How  much  sulphuric  acid  and  charcoal  are  needed 

for  100  liters  of  sulphurous  acid? 

27.  How   much    sulphuric    oxide    is   furnished    by   the 

oxidation  of  sulphurous  acid  as  follows  :  — 

a.  64  fibs.,  c.   i  ft., 

b.  32  g,  d.   1000  g? 
c 


26  CHEMICAL   PROBLEMS. 

28.  What  amount  of  oxygen  will  be  consumed  by  the 

operation  ? 

29.  What  amount  of  sulphuric  acid  corresponds  to  this  ? 
What  is  the  amount  of  the  combined  water  ? 

SULPHURIC    ACID. 

30.  How  much  (i)  sulphuric  oxide,  (2)  sulphuric  acid 

may  be  obtained  from  the  sulphurous  acid  which 
comes  from  the  following  amounts  of  sulphur : — 

a.  32  ft>s.,  c.  8  g,  e.  100  fts., 

b.  i  ft.,  d.  i  g,  /i  Kg? 

31.  How  obtain  the  quantity  of  sulphuric  oxide  which 

arises  from  a  given  quantity  of,  a.  sulphur,  b.  sul- 
phurous acid  ? 

32.  When    i    Kg  of  sulphur   and   the   like   amount  of 

sulphurous  acid  are  made  into  sulphuric  acid,  how 
much  sulphuric  oxide  may  this  contain  ?  How 
much  water  may  it  contain  ?  How  much  of  an  acid 
containing  90  per  cent,  of  a  pure  hydrated  acid  ? 

33.  How  much  sulphurous  acid  is  needed  to  form  sul- 

phurous oxide  as  follows  : — 

a.  80  g,  c.   I  Kg,  e.   11.335  g? 

b.  20  Bbs.,  d.  5  Bbs., 

34.  What  quantities  of  sulphurous  acid  and  water  are 

necessary  to  form  sulphuric  acid  as  follows : — 

a.  98  g,  c.  6.125  ft>s->  e-   14700  Kg? 

b.  7  Bbs.,  d.  1000  g, 

35.  How  much  oxygen  is  necessary  for  these? 

36.  How  many  cubic  centimeters  of  oxygen  are  needed 

to  convert  10  cu  m  of  sulphurous  acid  into  sul- 
phuric acid  ?  How  much  anhydride  and  hydrated 
acid  may  be  obtained,  and  how  many  liters  of  water 
are  necessary  for  the  latter  ? 

37.  How  much  of  an  acid  may  be  obtained,  which,  in 
addition  to  its  water  of  composition,  still  may  contain 
exactly  y2  its  molecular  weight  of  water  ? 


CHEMICAL    PROBLEMS.  27 

38.  What  yield  of  sulphuric  acid  will  these  amounts  of 

sulphur  give,  when  no  loss  takes  place  tf.  32  Kg,  b. 
1 6  cwt.  ?  How  much  of  an  acid  which  has  this  com- 
position: SO3,H2O  -f-  y2  water?  How  much  oxygen 
and  air  are  necessary,  and  how  much  water  remains 
in  the  acid  obtained?  (Oxygen  23  per  cent,  by 
weight  of  air.) 

39.  What  is  the  quantity,  by  theory,  of  sulphuric  acid 

resulting  from — 

a.  i  Kg,  b.  100  Bbs.  of  sulphur? 

How  many  cubic  centimeters  of  oxygen  and  air 
(with  20.9  per  cent.  O)  are  consumed  in  the  oxi- 
dation ? 

40.  What  amount  of  oxygen  will  be  consumed  to  yield 

the  English  sulphuric  acid  from  50  Kg  of  sulphur ; 
how  much  nitrogen  will  be  eliminated ;  how  much 
water  absorbed ;  how  much  sulphuric  acid,  and  acid 
of  the  composition  designated  in  38,  generated  ? 
The  quantity  of  oxygen  is  to  be  given  which  is 
consumed  by  the  burning,  and  the  amount  which  is 
necessary  in  the  subsequent  oxidation. 

41.  How  much  sulphur  must  be  burnt;  what  is  the  least 

amount  of  a.  oxygen,  b.  air  to  be  introduced ;  how 
much  water  must  be  combined,  to  obtain  1091.8  Kg 
sulphuric  acid  of  the  composition  given  in  38  above ; 
and  how  much  nitrogen  must  be  conducted  off? 
Oxygen  and  air  are  to  be  given  in  Kg  and  cubic 
meters.  (Composition  of  air  as  in  IV.  5,  6.) 


HYDROGEN    SULPHIDE. 

42.  What  is  the  percentage   composition   of  hydrogen 

sulphide  ? 

43.  What  is  the  spec.  grav.  of  hydrogen  sulphide,  (hydro- 

gen —  i),  if  by  the  union  of  the  elements  3  volumes 
will  be  condensed  to  2  ?  What  is  the  weight  of 
I  cu  dm  of  hydrogen  sulphide  ? 


28  CHEMICAL    PROBLEMS. 

44.  How  much  a.  sulphurous  acid,  and  b.  water  will  fur- 

nish hydrogen  sulphide  as  follows  : — 

a.  34  g,  b.   17  g,  c.  340  g,  d.  2  ft>s.  ? 

45.  How  much  a.  sulphurous  acid,  b.  water  will  furnish 

I  cu  m  of  hydrogen  sulphide  ?     (Ans.  in  grams  and 
liters.) 

46.  How  much  oxygen  will  be  consumed  by  this  opera- 

tion? 

47.  How   much    hydrogen    sulphide    may   be    obtained 

from  ferrous  sulphide  as  follows  : — 

a.  88  g,  c.  22  g,  e.  361.1  g, 

b.  4  Kg  400  g,       d.  i  ft).,  /.   I  Kg  ? 

48.  What  amount  of  sulphuric  acid  is  required  for  each 

ojf  these  decompositions  ? 

49.  How  much  ferrous  sulphide  and  sulphuric  acid  are 

required  to  give  hydrogen  sulphide  as  follows  : — 
a.  34ft>s.,  b.   139.5  g,   c.  3-24115  ft>s.,  d.   1523.2  g? 

50.  What  quantities  of  ferrous   sulphide  and   sulphuric 

acid  are  needed  to  give  a.   I  liter;  b.  0.25  cu  m  of 
hydrogen  sulphide? 


VI.— PHOSPHORUS. 

How  much  phosphorus  is  contained  in  phosphoric 
acid  (P3O5)  as  follows: — 
a.   142  g,         b.  35.5  Sbs.,         c.  2  Sbs.,         d.  5  g? 

What  is  the  least  amount  of  pure  carbon  to  be  taken 
for  a  liquid  containing  free  phosphoric  oxide  as  fol- 
lows, in  order  to  obtain  the  phosphorus  from  it : — 
a.  71  fibs.,        b.  I  ft).,  c.   10  g,          d.   i  Kg? 

Solution:  P2O5  -h5C  =  2P  +  5CO 

142         60         62          140 

For  142  parts  by  weight  60  parts  by  weight  of  carbon  are 
needed ;  for  I  part  by  weight  T6¥°^,  etc. 


CHEMICAL    PROBLEMS.  29 

3.  In  these  cases  how  much  phosphorus  and  carbonic 

oxide  will  form  ? 

4.  When  677.48  g  of  phosphoric  oxide  are  made  by 

the  burning  of  phosphorus,  how  much  phosphorus 
is  used ;  how  much  oxygen  ;  how  much  air  (accord- 
ing to  volume)  will  be  consumed  ? 

5.  How  much  phosphine  gas  may  be  obtained,  accord- 
ing to  theory,  by  means  of  phosphorus  as  follows : — 
a.   124  g,         b.  62  g,  c.  5  g,  d.  log? 

Solution :  3  (CaO,  H2O)  +  8  P  =  3  (CaO,P2O)  +  2  PH3. 

248  68 

68  parts  of  phosphine  may  be  obtained   from  248  parts 
of  phosphorus ;  ^F  from  I  part  of  phosphorus,  etc. 

6.  What  is  the  percentage  composition  of  phosphine  ? 

7.  How  many  liters  of  phosphine,  by  theory,  will  the 

following  amounts  of  phosphorus  yield  : — 
«•  ioo  g,  b.  33.333  g? 

8.  In  order  to  yield  phosphine  as  follows,  how  much 

lime,    water,    and    phosphorus    are    necessary    by 

theory : — 

«•  34  g,  b.  log,  c.   1.5232  g? 

9.  How  much  of  the  same  for — 

a.  i  liter,  b.  0.25  cu  m  ? 


VII.— CARBON. 

1.  How  much  (i)  carbon  mon-oxide,  (2)  carbon  di-oxide 

(carbonic  acid)  are  furnished  by  burning    12  g  of 
carbon  ? 

2.  How   much    of   the    same    by   burning   carbon    as 

follows : — 

a.  i  Kg,  c.   i  cwt,  e.   1500  g, 

b.  250  g,  d.  0.12  g,  /.  300  g? 

3.  What  amount  of  oxygen  will  be  consumed  for  this  ? 


30  CHEMICAL   PROBLEMS. 

4.  How  would  you  find  the  quantity  of  a.  carbon  mon- 

oxide, b.  carbonic  acid  which  may  arise  from  a 
given  quantity  of  carbon  ?  What  is  the  quantity  of 
oxygen  necessary  for  both  combustions  ? 

5.  What  is  the  weight  of  I  cu  m  a.  carbon  rnon-oxide, 

b.  carbonic  acid  ? 

6.  How  many  cubic  meters  of  oxygen  are  required  for 
the  complete  combustion   of   1000  Kg  of  carbon  ? 
How  much  air? 

7.  How  many  if  only  carbon  mon-oxide  is  obtained  ? 

8.  How    many    cubic    centimeters    a.    carbonic    acid, 
b.  carbon  mon-oxide  will  be  obtained  in  examples 
6  and  7  ? 

9.  From  the  following  quantities  of  carbonate  of  lime, 

how  much  carbonic  acid  may  be  obtained : — 

a.  100  g,  c.  25  Bbs.,  e.  1000  Kg, 

b.  i  Kg,  d.  I  g,  /.  227.3  Kg? 

10.  How  much  carbonic  acid  may  be  obtained  from  a 

sufficient  quantity  of  lime  by  means  of — 

a-  8-793  g  of  hydrochloric  acid,     b.   11.805   g  sul- 
phuric acid  ? 

11.  How  much  carbon  mon-oxide  maybe  obtained  by 

conducting  the  generated  gas  over  heated  carbon  ? 

12.  A  sufficient  quantity  of  calcium  carbonate  will  yield 

how  much  carbonic  acid  by  means  of — 

a.  233^  Bbs.,  b.  4666.667  g, 

of  a  muriatic  acid  containing  30  per  cent,  of  pure 
hydrochloric  acid  ? 

13.  What  amount  of  carbon  mon-oxide  will  be  obtained 

by  passing  30  Bbs.  of  carbonic  acid  over  heated  char- 
coal, and  how  much  will  the  weight  of  the  tube  be 
diminished  or  increased  ? 

14.  What   amount   of    carbonic    acid    must   be    passed 

through  a  vessel  which  contains  5.625  g  of  heated 
charcoal  until  this  entirely  disappears,  if  it  be  granted 
that  the  whole  amount  of  carbonic  acid  should  be- 


CHEMICAL    PROBLEMS.  31 

come  oxide,  and  the  charcoal  a  pure  carbon ;  and 
how  much  carbon  mon-oxide  do  we  obtain  ? 

15.  How  much  carbon  mon-oxide  may  be  obtained  from 

a.  90  g  of  oxalic  acid  when  the  pure  acid  is  taken 
without  the  water  of  crystallization,  b.  126  g  if  2 
molecules  of  water  are  present  ? 

1 6.  About  how  much  heavier  will  the  vessel  with  the 

lime  water  become,  in  which  the  gas  of  the  pre- 
ceding quantities  was  washed  ?  What  will  still  be 
given  off  from  it  ? 

17.  a.  How  many  cubic  decimeters  of  carbon  mon-oxide 

may  be  obtained  from  I  Kg  840  g  neutral  potassium 
oxalate?  b.  How  many  from  I  Kg  460  g  acid 
potassium  oxalate? 

/Formula  of  the  neutral  salt  K2C2O4    -f-  H2O.  \ 
V  acid         "    KHC2O4  +  H2OJ 

1 8.  What  quantity  of  sulphuric  acid  is  needed  to  expel 

the  carbonic  acid  from  the  following  quantities  of 
calcium  carbonate : — 

a.  100  g,  c.  3  g,  e.   uofbs.  ? 

b.  10  Ibs.,  d.  150  Kg, 

19.  How  much  sulphuric  acid  is  needed  for  an  equal  quan- 

tity, if  it  may  yet  contain  j£  its  molecular  weight  of 
water  in  addition  to  its  water  of  composition? 

20.  How  much  muriatic  acid,  containing  25  per  cent,  of 

hydrogen  chloride,  is  necessary  to  expel  the  carbonic 
acid  from  the  following  amounts  of  calcium  car- 
bonate : — 

a.  ico  g,  c.  3  g,  e.  no  R>s.  ? 

b.  10  fts.,  d,   150  Kg, 

21.  What  amount  of  pure  carbon  must  be  burnt  to  yield 

carbon  mon-oxide  as  follows  : — 

a.  28  g,  c.  80  g,  e.  0.5  g, 

b.  21  Sbs.,  d.   I  ft.,  /.   1 254.4  g? 

22.  What  amount   of  carbon   must   be  burnt  to   yield 

100  liters  of  carbon  mon-oxide? 


32  CHEMICAL    PROBLEMS. 

23.  How  much  carbon  must  be  burnt  to  produce  car- 
bonic acid  as  follows  : — 

a.  44  ft>s.,  c.  352  g,  e.  4  Kg  400  g, 

b.  22  g,  d.   1971.2  g,  /  122.1  g? 

24.  How  much  to  produce,  a.  1860.1  cu  m,  b.  1000  cu  m? 

25.  What  quantities  of  acid  potassium  oxalate  and  sul- 

phuric acid  are  needed  to  yield,  a.  55.8  cu  dm, 
b.  74.4  cu  m  of  carbon  mon-oxide  ? 

Solution :  First  it  is  necessary  to  find  the  weights  of  the  required 
gases,  then,  according  to  the  formula  in  example  17,  that 
of  acid  potassium  oxalate,  and  afterwards  that  of  the 
sulphuric  acid,  of  which  two  molecules  by  weight  were 
necessary. 

26.  How  much   calcium   carbonate,  muriatic  acid   con- 
taining 30  per  cent,  of  hydrochloric  acid  gas,  and 
carbon   are   needed  to   yield   30  g  of  carbon  mon- 
oxide ? 

27.  How  much   calcium   carbonate  and  sulphuric  acid 
with  y2  the  molecular  weight  of  water,  besides  the 
hydrate,  are  needed  for  I  cu  m  of  carbonic  acid  ? 

28.  What  amount  of  calcium   carbonate  would  be   re- 

quired for  the  evolution  of  carbonic  acid,  when 
1000  liters  of  water  under  a  pressure  of  4  atmo- 
spheres shall  have  been  saturated  by  the  evolved 
gases  ?  How  much  sulphuric  acid  is  necessary  for 
this? 

CARBON    BISULPHIDE. 

29.  How  much  sulphur  must  be  transformed  into  vapor 
to  yield  carbon  di-sulphide  as  follows : — 

a-  76  g>  ^-38  S)s.,         c.  5  Bbs.,          d.  20  g? 

How  much  lighter  will  the  tube  containing  the  car- 
bon become  ? 

HYDRO  CARBONS. 

30.  What  is  the  percentage  composition  of  ethylene  gas  ? 

31.  What  is  the  percentage  composition  of  mine  gas? 


CHEMICAL    PROBLEMS.  33 

32.  How  much  oxygen  is   needed  to  burn    I   cu  m  of 

ethylene  and  what  results  ? 

33.  How  much  oxygen  is  required  to  burn  I  cu  dm  of 

mine   gas ;    and  how  much   of  both   of  the  burnt 
products  will  be  obtained  ? 


VIII.— FLUORINE. 

1.  What  is  the  percentage  composition  of  hydrofluoric 

acid? 

2.  How  much  hydrofluoric  acid  may  be  obtained  from 

fluorspar  as  follows  : — 

a-  78  g>  b-  39  E>s.,         c.  25  g,          d.  i  Kg? 

3.  What  amount  of  hydrofluoric  acid,  containing  36  per 

cent,  of  the  acid  contents,  may  be  obtained  from  a 
sufficient  quantity  of  fluorspar  by  means  of  sulphuric 
acid  as  follows  : — 

a.  98  fos.,  b.  49  g, 

c,   12.25  g>  d.   12  g? 

4.  How  much  fluorspar  and  sulphuric  acid  are  required 
to  yield  hydrogen  fluoride  as  follows : — 

a.  20  fibs.,  d.  30  g, 

b.  10  g,  e.  i  Kg, 

c.  i  g,  /.   I  ft).  ? 

5.  What  amount  of  fluorspar  and  sulphuric  acid  are 

necessary  to  yield  the  following  quantities  of  hydro- 
gen fluoride  containing  20  per  cent,  of  water,  and 
how  much  water  will  be  consumed  : — 

a.  25  g,  d.  i  g, 

b.  35  Bbs.,  e.  i  ft).  ? 

c-  5  g, 

6.  What  amount  of  calcium  sulphate  will  be  obtained  by 

the  preparation  of  hydrogen  fluoride  as  follows : — 

a.  40  g,  c.   I  g, 

b.  20  ft)s.,  d.  30  g  ? 


34  CHEMICAL   PROBLEMS. 

IX.— POTASSIUM. 

POTASSIUM    HYDRATE. 

1.  What  amount  of  potassium  hydrate  will  the  following 

quantities  of  potassium  carbonate  yield  : — 

a.  138  Ibs.,  c.   i  Kg, 

b.  69  Ibs.,  d.  200  Ibs.  ? 
Solution:  K2O,CO2  -f  CaO,H2O  =  K2O,H2O  -f  CaO,CO2 

138  74  112  100 

Or,  K2CO3  +  H2CaO2  =  2  (KOH)  -f  CaCO3 

138  74  112  100 

2.  How  much  (i)  calcium  oxide,  (2)  calcium  hydrate 
are  necessary  for  this ;   and  how  much  potassium 
carbonate  remains  behind  ? 

3.  What  amount  of  burnt  lime  and  potassium  carbonate 

are  required  to  yield  caustic  potash  as  follows : — 

a.  112  Ibs.,  c.  25  g, 

b.  i  lb.,  d.  811.6  g? 

POTASSIUM    CARBONATE. 

4.  How  much  tartar  must  be  heated  to  furnish  pure 
potassium  carbonate  as  follows  : — 

a.  69  g,  d.   I  Kg, 

b.  138  Ibs.,  e.  25  g? 

c.  i  lb., 

Formula  of  cream  of  tartar  : — 
KHC4H406  or,  C4H4O4 
K,H 

5.  How  much  potassium  chloride  must  be  precipitated 

with  tartaric  acid,  to  obtain  the  necessary  quantities 
of  tartar  for  yielding  pure  potassium  carbonate  as 
follows : — 

a.  6  g,  d.  i  Kg, 

b.  loo  g,  e.  25  g? 

c.  10  Ibs., 


CHEMICAL    PROBLEMS.  35 

Solution :  It  is  easy  to  reckon  the  last  quantity  and  from  this  the 
quantity  of  potassium  chlorate,  yet  this  is  not  necessary, 
since  the  quantity  of  potassium  remains  unchanged  in  all 
compounds.  We  can  determine  directly  the  chloride 
of  potassium  from  the  carbonate,  in  doing  which  we  must 
bear  in  mind  the  unlike  number  of  atoms. 

POTASSIUM    NITRATE. 

6.  What  is  the  percentage  composition  of  saltpeter  ? 

7.  How  much  potassium  nitrate  can  be  obtained  from 

calcium  nitrate  as  follows  : — 

a.  1000  g,  c.  1000  Ibs.  ? 

b.  12  cwt., 

8.  How  much   potassium    carbonate   is    necessary  for 

this? 

9.  What  quantities  of  calcium  nitrate  and  potassium  car- 

bonate are  needed  to  yield  saltpeter  as  follows : — 

a.  202  Ibs.,  d.   14  cwt,  78  Ibs., 

b.  100  Ibs.,  e.  1000  cwt.  ? 

^   1231-7  g, 

10.  What  is  the  least  quantity  of  calcium  carbonate  that 

must  be  mixed  with  1000  hundred-weight  of  a 
substance  containing  12  per  cent,  nitrogen,  for  the 
formation  of  saltpeter,  and  how  much  saltpeter  may 
be  obtained  according  to  theory  ? 

11.  How  much  potassium  nitrate  and  sulphuric  acid  are 

needed,  and  how  much  water  must  be  consumed  to 
yield  nitric  acid  as  follows  containing  8o£/7  per  cent, 
of  anhydride : — 

a.  72.71  fts.,  b.  22.3  g? 

12.  What  amount  of  potassium  nitrate,  sulphuric  acid, 

and  water  are  necessary  to  furnish  I  Kg  of  aqua- 
fortis containing  28.5  per  cent,  of  nitric  anhydride  ? 

13.  How  much  sulphur  and  carbon,  supposed  to  be  pure, 

must  be  mixed,  by  theory,  with  100  parts  of  salt- 
peter in  order  to  yield  gunpowder  ? 

14.  What  is  the  percentage  composition  of  gunpowder,  ac- 

cording to  theory,  when  mixed  with  pure  materials? 


36  CHEMICAL    PROBLEMS. 

15.  How  much  of  the  individual  products  may  be  ob- 
tained by  burning  a.   100  Ibs.,  b.  5  g  of  such  gun- 
powder ? 
Solution  :  K2O,N2O5  -f3C-j-S  =  K2S  +  2N-f3  CO2 


270  no         28  132 

1  6.  What  volume,  without  regard  to  the  raising  of  tem- 

perature, do  these  gases  occupy  in  these  cases  ? 
17.  How  much   gunpowder  must  explode,  if  the  gas- 

forming  products,  reduced  to  o°  and  760  mm,  occupy 

a  space  of  a.   100  cu  m,  b.  50  cu  dm  ? 
1  8.  Reckon  in  every  case  the  contents  per  volume  of 

both  gases  evolved  by  this  means. 

POTASSIUM    CHLORATE. 

19.  How  much  chlorine  is  necessary  to  yield  potassium 

chlorate  with  potassium  hydrate  as  follows  :  — 

a.  336  Ibs.,  c.   i  lb., 

b.  33.6  g,  d.  200  g? 

20.  What  is  the  entire  product  of  both  salts  ? 

21.  What  amount  of  potassium  chlorate  is  contained  in 

these  quantities  ? 

22.  How  much  potassium  chloride  can  we  obtain  from 

a.  loo  pts.  of  the  product,  b.  I  pt.  of  potassium 
chlorate  ?  The  two  salts,  therefore,  bear  what  ratio 
to  each  other  ? 

23.  How  much  potassium  hydrate,  black  oxide  of  man- 
•ganese,  and  hydrochloric  acid  are  needed  to  yield 

potassium  chlorate  as  follows  :  — 

a.  122:5  g,  c.   I  Kg, 

b.  I  lb.,  d.  20  Ibs.  ? 

"LIVER   OF   SULPHUR." 

24.  What  quantity   of  potassium   carbonate  should   be 

taken,  with  sulphur  as  follows,  in  order  to  obtain 
liver  of  sulphur  :  — 

a.  512  g,  c.  8  Kg, 

b.  10  g,  d.  100  Ibs.? 


CHEMICAL   PROBLEMS.  37 

25.  How  much  liver  of  sulphur  may  be  obtained,  and 

carbonate  liberated  ? 

26.  What  amount  of  pentasulphide  of  potassium  is  con- 

tained in  the  obtained  amounts  of  liver  of  sulphur  ? 

27.  What  per  cent.  ? 

28.  a.  How  is  the  quantity  of  sulphur  contained  in  the 

sulphide  of  potassium  related  to  that  contained  in 
the  potassium  sulphate  ? 

b.  What  amount  of  the  sulphur  taken  may  be  ob- 
tained as  milk  of  sulphur,  by  the  use  of  liver  of 
sulphur  with  hydrogen  chloride  ? 

29.  The  sulphur  and  potassium  carbonate,  that  are  heated 

together,  bear  what  relation  to  each  other  ? 


X.— SODIUM. 

(The  examples  which  are  related  to  the  preceding, 
and  are  similar  to  those  of  potassium,  are  omitted 
in  this  place.) 

When  you  are  dealing  with  a  chemical  reaction,  in 
which  caustic  soda  or  caustic  potash  shows  the  same 
phenomena,  which  of  the  substances  is  it  advisable 
to  employ,  if  the  price  is  the  same  ? 
If  the  price  of  potassium  carbonate  and 

a.  Carbonate  of  soda  free  from  water, 

b.  containing  water 

is  the  same,  which  of  the  two  substances  is  it  better 
to  use,  other  things  being  equal  ? 

a.  How  must  the  prices  of  the  substances  stand,  if 
in  this  respect  it  is  immaterial  which  of  the  two  is 
used? 

b.  How  must  the  price  of  the  anhydrous   sodium 
carbonate,  regardless  of  other  circumstances,  propor- 
tion itself  to  that  of  the  hydrous,  if  only  the  real 
value  be  considered  ? 


38  CHEMICAL   PROBLEMS. 

4.  What  is  the  percentage  composition  of  sodium  car- 

bonate— 

a.  effloresced, 

b.  crystallized? 

5.  How   much    soda  will  the    following   quantities    of 

sodium  sulphate  yield  : — 

a.  426  Ibs.,  c.  71  Kg,  e.  1000  Kg, 

&  213  Ibs.,  d.   1000  Ibs.,  f.  70  cwt., 

if  the  following  formulae  be  made  the  basis  of  the 
soda  process : — 

3  (Na20,S03)  +  4  (CaO,CO2)  +  1$  C  =? 

3  (Na2O,CO2)  -f  3  (CaS)  -f-  CaO  +  14  CO? 
Or,  3  Na2SO4  +  CaCO3  +  13  C  = 

3  Na2CO3  +  3  CaS  +  CaO  -f  14  CO  ? 

6.  How  much   calcium   carbonate  and  carbon  are  re- 

quired by  this  acceptance,  according  to  theory,  for  the 
decomposition  of  the  above  quantities,  pure  material 
supposed  ? 

7.  How   much   anhydrous    sodium    sulphate,    calcium 

carbonate,  and  carbon,  under  like  conditions  are 
needed  to  yield  anhydrous  carbonate  of  soda  as 
follows : — 

#.  318  Ibs.,  c.  1000  Ibs., 

b.  746.48  Kg,  d.  500  Kg? 

8.  What  amounts  of  crystallized  sodium  sulphate,  car- 

bonate of  lime,  and  carbon,  under  the  same  con- 
ditions, are  necessary  according  to  theory  to  yield 
crystallized  sodium  carbonate  as  follows  : — 
#.  858  Ibs.,  c.   1000  cwt, 

b.  143  cwt,  d.  i oo  Kg? 

9.  How  much  sodium  chloride  must  be  employed  in 

the  operation  to  yield  the  desired  quantities  in  7, 
and  how  much  muriatic  acid  gas  will  be  set  free  ? 
IO.  What  are  the  quantities  of  the  different  materials 
that,  under  the  same  suppositions,  are  necessary  for 


CHEMICAL    PROBLEMS.  39 

the  production  of  100  Kg  of  anhydrous  carbonate 
of  soda,  and  what  are  the  resulting  products  by 
this  operation? 


BI-CARBONATE  OF   SODA. 

11.  What  is  the  percentage  composition  of  bi-carbonate 

of  soda  ? 

12.  How  many  cu  cm  of  carbonic  acid,  at  o°,  does   I   g 
bicarbonate  of  soda  yield,  when  it  is  decomposed  by 
the  excess  of  acid  ? 

13.  How  many  cu  dm  carbonic  acid  can  be  obtained 

from  a  solution  which  contains  53  g  of  anhydrous 
carbonate  of  soda,  if  this  be  converted  into  acid 
salts  ? 

14.  In  what  proportion  must  crystallized  and  anhydrous 

carbonate  of  soda  be  mixed,  that  the  mixture  may 
receive  the  required  quantity  for  the  production  of 
the  acid  salts  ? 

15.  How  many    cubic  decimeters  of  carbonic  acid  are 

evolved  by  heating  I  Kg  bi-carbonate  of  soda  ? 

1 6.  In  what  proportion  should  bi-carbonate  of  soda  and 

tartaric  acid  (C4H6O6)  be  mixed,  if  after  the  dissolu- 
tion, neither  of  them  shall  remain  in  excess  ? 

BORAX. 

1 7.  What  is  the  percentage  composition  of  borax  ? 

1 8.  What  is  the   percentage   composition   of  tHe   octa- 

hedral borax  ? 

19.  How  much  borax  can  be  obtained  from  a.  1500  cwt., 

b.  1000  Kg  of  a  liquid  containing  3  per  cent  boracic 
acid,  and  how  much  anhydrous  carbonate  of  soda  is 
necessary  for  this  ? 

20.  What  amount  of  octahedral  borax  is  needed  to  obtain 

borax  glass  as  follows  : — 

a.  100  g,  b.  20  Ibs.  ? 


40  CHEMICAL   PROBLEMS. 

21.  What   is   the   percentage    composition   of  common 
salt— 

a.  in   100  parts? 

b.  for  100  parts  of  sodium  ? 

c.  "  "      chlorine? 


XI.— AMMONIUM. 

1.  In  what  relation  do  the  gases  stand  by  volume  of 

the  decomposed  products  of  mercuric  di-ammonide 
(Hg[NH4]2)?  In  what  relation  do  the  same  stand 
by  weight  ? 

2.  What  quantities  of  ammonium  sulphate  and  common 

salt  are  required  to  yield  ammonium  chloride  as 
follows : — 

a.  100  cwt.,  d.  10  Ibs., 

b.  80  g,  c.  4  g  ? 

3.  How  much  neutral  ammonium  carbonate  (di-ammo- 

nium  carbonate)  will  be  necessary,  how  much  gypsum 
decomposed,  and  how  much  sulphate  of  soda  formed, 
to  yield  100  Ibs.  of  ammonium  chloride? 

4.  How  much  sesqui-carbonate  of  ammonia  is  necessary 
to  form  90.678  g  ammonium  chloride,  and  how  much 
hydrochloric  acid  will  be  neutralized  by  these  means 
from  these  quantities  ? 

5.  How  much  of  a  liquid,  containing  15  per  cent,  sesqui- 

carbonate  of  ammonium,  is  required  to  yield  100  Ibs. 
of 'sal-ammoniac,  and  how  much  muriatic  acid,  of 
20  per  cent,  acid  content  of  hydrochloric  acid,  is 
necessary  for  this  ? 

6.  What  is  the  percentage  composition  of  a  liquid  in 

sesqui-carbonate  of  ammonium,  of  which  581.915  g 
are  necessary,  in  order  to  neutralize  40  g  of  a  muriatic 
acid  containing  18  per  cent,  of  hydrochloric  acid? 

7.  What  is  the  percentage  amount  of  ammonia  in  a 

liquid,  if  2.5  g  yield  0.27537  g  of  sal-ammoniac, 
with  an  indefinite  amount  of  muriatic  acid  ? 


CHEMICAL   PROBLEMS.  41 

XII.— BARIUM. 

1.  How  much  barium  sulphide,  barium  hydrate,  barium 

nitrate,  and  barium  chloride  must  be  obtained,  accord- 
ing to  theory,  from  barium  sulphate  as  follows : — 

a.  233  Ibs.,  c.  100  g, 

b.  116.5  g,  d-  l  K£? 

2.  How  much  charcoal  is  necessary  for  the  reduction 

of  these  quantities,  and  how  much  carbonic  oxide 
will  be  formed  ? 

3.  What  amount  of  heavy  spar  is  needed,  and  what  is 

the  least  amount  of  charcoal  that  must  be  added,  to 
yield  barium  chloride  as  follows  : — 

a.  104  g,  c.  250  g, 

b.  47.318  g,  d.   100  Ibs.? 

4.  What  quantity  of  barium   sulphate  and  potassium 

carbonate  must  be  heated  together  to  yield  barium 
carbonate  as  follows  : — 

a.  197  g,  c.   loo  Ibs., 

b.  98.5  Ibs.,  d.  i  Kg? 

5.  How  much  barium  chloride  is  in  a  liquid,  which  will 

be  precipitated  immediately  by  4.71154  g  of  sul- 
phuric acid  ? 

6.  What  per  cent,  of  anhydrous  sulphuric  acid  is  con- 

tained in  a  liquid,  of  which  21.5  g  are  required  for 
the  precipitation  of  5.6  g  of  barium  chloride? 

7.  Will   still   another  compound   be   set   free   by  this 

precipitation  ?     What  and  how  much  ? 

8.  What  per  cent,  of  barium  nitrate  may  a  substance 

contain,  of  which  19.98  g  yield  a  precipitate  with  a 
sulphuric  acid  compound  which  weighs  0.89183  g? 

9.  If  it   is    required   to   precipitate   4.5    g    of  barium 

chloride  by  means  of  carbonic  acid,  how  much 
ammonium  oxide,  in  the  form  of  ammonium  and 
H2O,  must  be  added  to  the  solution  ?  How  much 
secondary  ammonium  carbonate  is  required  for  the 
preparation  ? 
D 


42  CHEMICAL    PROBLEMS. 

10.  How  much  crystallized  sodium  carbonate  and  barium 

chloride  are  needed  to  yield  barium  carbonate  as 

follows : — 

a.  20  g,  b.   I  lb.,  c.   I  Kg  ? 

11.  Will  a  bye-product  be  obtained,  and  how  much  ? 


XIII.— CALCIUM. 

1.  How  much  burnt  lime  may  be  obtained  from  calcium 

carbonate  as  follows  : — 

a.  100  Ibs.,  c.   i  lb., 

b.  1000  Kg,      ..  d.  2$  g? 

2.  How  much  calcium  hydrate  may  be  obtained  from 

the  same  quantities  ? 

3.  What  quantities  of  calcium  carbonate  must  be  burnt 
to  yield  burnt  lime  as  follows  : — 

#.  56  Ibs.,  c.  140  Kg,  e.  1000  Kg, 

b.  14  cwt,  d.  100  Ibs.,  /.  5  cwt.  ? 

4.  How  many  cu  m  of  carbonic  acid  will  be  liberated 
in  each  case  ? 

5.  How  much  H2O  is  necessary  to  slake  these  quantities 

of  lime  ? 

6.  How  many  cu  m  of  carbonic  acid  can  a  milk  of 

lime  absorb  which  contains  lime  as  follows  : — 

a.  56  Ibs.,  c.  100  Kg, 

b.  100  Ibs.,  d.  1 4  Kg? 

7.  When  a  pure  calcium  carbonate  is  formed,  calcium 

chloride  may  be  precipitated  with  sodium  carbonate. 
How  much  of  both  are  required  to  yield  calcium 
carbonate  as  follows  : — 

a.  40  g,  c.  100  g, 

b.  i  Kg,  d.  5  Ibs.  ? 

8.  What  is  the  percentage  composition  of  a.  unburnt, 

b.  burnt  gypsum  ? 


CHEMICAL   PROBLEMS.  43 

9.  How  much  water  is  necessary  to  harden  completely 
the  following  amounts  of  burnt  gypsum,  if  it  be 
granted  that  no  loss  is  sustained : — 

a.  68  Ibs.,  c.  i  Kg, 

b.  17  g,  d.  50  g? 

10.  What  amount  of  acid  calcium  phosphate  is  necessary 

to  yield,  by  precipitation,  anhydrous  phosphoric  acid 

as  follows : — 

a.  142  g,  b.  50  Ibs.,  c.  I  Kg? 

11.  What  is  the  percentage  composition,  according  to 

theory,  of  anhydrous  calcium  chloride,  correspond- 
ing to  the  formula  ? 

12.  What  amount  of  chlorine  and  lime  is  necessary  to 

yield  anhydrous  chloride  of  lime  as  follows,  accord- 
ing to  theory,  if  it  be  granted  that  no  loss  is  sus- 
tained : — 

a,  254  Ibs.,  c.  25  g, 

b.  127  g,  d.  100  Kg? 

13.  How  many  liters  or  cu  m  of  chlorine  are  necessary, 
by  the  same  suppositions,  for — 

a.  254  g,  b.  loo  Ibs.,  c.  100  Kg, 

calcium  chloride  ? 

14.  What  quantity  of  hydrochloric  acid  and  black  oxide 

of  manganese  are  required  to  evolve  the  necessary 
chlorine  in  example  12? 

15.  How   much   calcium    hydrate   and   black   oxide   of 

manganese,  and  how  much  muriatic  acid  of  30  per 
cent,  acid  content,  are  necessary  to  yield  1000  Ibs. 
of  calcium  chloride;  if  this  be  taken  anhydrous 
and  contain  only  35  per  cent,  of  the  whole  amount 
of  chlorine  ? 

1 6.  What  quantity  of  black  oxide  of  manganese,  25  per 

cent  muriatic  acid,  and  calcium  hydrate  are  re- 
quired, under  the  known  conditions,  to  yield  lOoKg 
of  a  chloride  of  lime  which  contains  64  per  cent, 
of  calcium  hydrate  ? 


44  CHEMICAL   PROBLEMS. 

17.  If,  by  a   calcium    determination,   2.5   g  of  calcium 

carbonate  are  obtained  by  heating  the  precipitated 
calcium  oxalate,  what  amounts  of — 

a.  lime, 

b.  calcium  chloride, 

c.  "        sulphate, 
may  be  calculated  out  of  this  ? 

1 8.  What  per  cent,  if  7.5  g  be  taken  for  the  analysis  ? 


XIV.— MAGNESIUM. 

1.  What  quantity  of  magnesite   is    required   to   yield 

1000  Kg  of  crystallized  magnesium  sulphate? 

2.  What  is   the   percentage    composition   of  magnesia 

alba,  the  formulae  producing  it  corresponding  to — 

MgO,H20  +  3  (MgO,C02)  +H20? 
Or,  Mg02H2  +  3  C03Mg  -f  H2O? 
Or,  C3012Mg4H4? 

3.  How   much   crystallized   magnesium    sulphate   and 
potassium  carbonate  are  needed  to  yield  magnesia 
alba  as  follows  : — 

a.  164  g,  c.   100  Ibs., 

b.  41  Ibs.,  d.  1000  Kg? 

4.  Is  the  quantity  of  obtained  magnesia  and  potassium 

sulphate,  bearing  in  mind  the  elimination  of  the 
water  of  crystallization,  equal  to  the  sum  of  the 
employed  substances  ?  In  what  does  the  difference 
lie  ?  Loss  or  gain  ?  Which  material  is  the  cause  ? 

5.  How  much   magnesia  alba  (of  the  composition  as 

above)  must  be  heated  to  yield  pure  magnesia 
as  follows : — 

a.  20  Ibs.,  c.   100  Ibs., 

b.  4  g,  d.  1000  g? 


CHEMICAL    PROBLEMS.  45 

6.  What   is   the   percentage   composition  of  ammonia 

magnesium  phosphate?  What  per  cent,  of  this 
precipitate  remains  behind  by  heating  ? 

7.  How  much   magnesia  was    contained   in   a   liquid, 
which,  by  the  precipitation  with  sodium  phosphate 
and  ammonia,  gave  precipitates  as  follows  : — 

a.  1. 1 1  g,  b.  3.7  g,  d.  2.5  g? 

8.  What  per  cent,  (i)  phosphoric  acid,  (2)  anhydrous 

sodium  phosphate  do  the  substances  contain,  of 
which  2.25  g  gave  a  precipitate  with  Epsom  salts 
and  ammonia,  which  after  heating  left  residues  as 
follows : — 

a.  i.i  i  g,  c.  0.37  g, 

b.  1.85  g,  d.  0.074  g? 


XV.— ALUMINIUM. 

1.  What  per  cent,  of  a.  alumina,  b.  alumina  sulphate 

do  (i)  potash   alum,  (2)  soda   alum,  (3)    ammonia 
alum  contain  ? 

2.  a.  What  per  cent,  of  water  do  these  alums  contain  ? 
b.  What  per  cent,  of  their  weight  will  be  left  by 
heating  ? 

3.  What  is  the  percentage  composition  of  feldspar? 

4.  What  amount  of  potash  alum  and  potassium  car- 

bonate are  needed  to  yield  alumina  as  follows,  and 
how  much  carbonic  acid  will  be  set  free : — 

a.  102.8  g,  c.  10  Ibs., 

b.  25.7  Ibs.,  d.  i  Kg? 


XVI.— IRON. 

I.  What  per  cent,  of  iron  must  be  left  from  the  follow- 
ing earths  taken  pure,  if  there  is  no  loss : — 

a.  magnetic  iron  ore,  c.  brown  iron  ore, 

b.  hematite,  d.  spathose  iron  ore  ? 


46  .CHEMICAL   PROBLEMS. 

2.  How  much  anhydrous  ferrous  sulphate  is  employed 

to  obtain,  by  oxydation,  precipitation,  and  heating, 
the  following  amounts  of  sesqui-oxide  of  iron : — 

a.  1 60  g,  c.   I  lb., 

b.  4  g,  d.  20  g  ? 

3.  How  much  iron  will  be  oxydized  when  rust  has 
formed  as  follows,  if  it  be  accepted  that  this  contains 
half  as  much  oxygen  in  the  hydrate  as  in  the  ferric 
oxide : — 

«•  93-5  g,  c.  9.35  g, 

b.   I  g,  d.   10  g? 

4.  What  quantity  of  iron  of  2.5  per  cent,  carbon  is  dis- 

solved by  means  of  muriatic  acid  to  obtain,  after 
oxydation,  precipitation,  and  heating  ferric  oxide 
as  follows : — 

a.  i  g,  c.  7.5  lbs.f 

b.  5  g,  d.  40  g  ? 

5.  What  per  cent.  a.  iron,  b,  ferric  oxide,  c.  ferrous  sul- 

phate, d.  ferrous  carbonate  may  a  substance  contain, 
2-35 J  5  g  of  which  yield  by  precipitation  and  heating 
(i)  0.4782  g,  (2)  0.1594  g  of  ferric  oxide? 

6.  How  much  green  vitriol  may  be  obtained  from — 

a.  60  cwt,  c.  30  Kg, 

b.  1000  Ibs.,  d.  100  Kg, 
of  iron  pyrites  ? 

7.  What  amount  of  green  vitriol  may  be  obtained  from 

sulphur  residue  as  follows  : — 

a.  648  Ibs.,  c.   1000  Kg, 

b.  100  cwt,  d.  60  Ibs.  ? 

8.  How  many  cu  m  of  oxygen  will  be  consumed  in 
the  formation  of  green  vitriol  in  example  6?     How 
much  water  must  be  taken  up  ? 

9.*  How  much  of  both  for  example  7  ? 
IO.  How  much  sulphur  is  lost  in  example  6?     How 
much  oxygen  is  required  for  the  same  ? 


CHEMICAL   PROBLEMS.  47 

11.  What  amount  of  crystallized  green  vitriol,  is  to  be 

ignited,  after  its  dehydration,  in  order,  without  pre- 
vious roasting,  to  yield  anhydrous  sulphuric  acid 
as  follows  : —  • 

a.  40  Ibs.,  c.  200  g, 

b.  20  g,  d.  i oo  Ibs.  ? 

12.  How  much  is  necessary  if  it  has  been  previously 

roasted  ? 

1 3.  What  quantity  of  water  must  be  expelled  from  every 

100  parts  for  the  obtained  anhydrous  acid  a.  when 
it  has  not  been  roasted,  b.  when  it  has  been  roasted  ? 

14.  How  much  potassium   sulphate  and   neutral    ferric 
sulphate  are  necessary  to  yield — 

a.  503  g,  b.  20  g,  c.   i  lb., 

potash  iron  alum  ? 

15.  What  is  the  percentage  composition  of  crystallized 

ferro-cyanide  of  potassium  ? 

1 6.  What  of  ferri-cyanide  of  potassium  ? 

17.  How  much   iron  and  potassium  carbonate  will  be 

required  to  yield — 

a.  211  g,  b.  100  Ibs.,  c.  1000  Kg, 

of  ferro-cyanide  of  potassium,  if  there  is  no  loss? 

1 8.  What  amount  of  ferro-cyanide  and  ferric  chloride, 

both  anhydrous,  are  necessary  to  yield — 

a.  860  g,  c.   100  Ibs., 

b.  43  Ibs.,  d.   1000  Kg, 

of  Prussian  blue  ? 

19.  How  much  pure  ferrous-cyanide  will   be  obtained 

from — 

a.  184  g,  c.   100  g, 

b.  46  Ibs.,  ^.552  Ibs., 

of  ferro-cyanide  (anhydrous),  when  ferrous  sulphate 
is  employed  and  a  pure  compound  is  precipitated  ? 
How  much  of  the  iron  salt  is  necessary  for  this 
operation  ? 


48  CHEMICAL    PROBLEMS. 

20.  What   amount   of   ferrous-cyanide   is    necessary   to 

make  Prussian-blue  as  follows,  by  the  oxydation  of 
the  cyanide,  when  this  is  freed  from  the  mixed  oxide 
by  nitric  a€id  : — 

a.  860  g,  c.   ico  g, 

b.  21$  g,  d.  loco  Ibs.  ? 
What  is  the  weight  of  the  oxide  to  be  removed  ? 

21.  What  quantity  of  ferro-cyanide  and  ferrous  sulphate, 

both  anhydrous,  are  required  to  yield — 

a.  430  Ibs.,  c.  1000  cwt, 

b.  100  Ibs.,  d.  500  Kg, 

of  Prussian-blue,  if  the  precipitate  thrown  down  by 
the  mixing  of  both  compounds  be  entirely  freed  from 
the  oxide,  and  ferrous-ferric  cyanide  be  accepted  as 
pure? 

22.  How  many  cu  dm  of  chlorine  must  act  upon  the 
solution  of — 

a.  422  g,  b.  20  g,  c.  2.5  Kg, 

of  crystallized  ferro-cyanide  to  convert  this  into 
ferri-cyanide  of  potassium  ? 

23.  What  amount  of  ferri-cyanide  of  potassium  may  be 

obtained  in  these  cases  ? 

24.  How  much  crystallized  ferro-cyanide  must  be  taken 
to  yield  ferri-cyanide  as  follows  : — 

a.  329  g»  c.  25  g, 

b,  10.3  Ibs.,  d.   I  Kg? 


XVII.— MANGANESE. 

What  quantity  of  carbonic  oxide  will  be  liberated 
when — 

a.  87  g,  c.  2.18  Ibs., 

b.  4.36  g,  d.   10  g, 

of  manganese  di-oxide  are  mixed  with  neutral  potas- 
sium oxalate  and  covered  with  sulphuric  acid  ? 


CHEMICAL    PROBLEMS.  49 

2.  How  much  manganese  di-oxide  do  four  manganese 

tests  contain,  of  which  every  3.27  g  by  these  tests 
yield  carbonic  acid  as  follows : — 

a.  2.24  g,  c.  3  g, 

b.  2.50  g,  d.  1.25  g? 

3.  About  how  much  lighter  will  a  strip  of  copper  be- 

come if  it  be  laid  in  a  mixture  of  muriatic  acid  and 
the  following  quantities  of  manganese  di-oxide : — 

.«•  43-5  g,  b.  1.45  g,  c.    i  g? 

4.  What  per  cent,  of  manganese  di-oxide  do  the  four 

manganese  tests  contain,  by  which  a  strip  of  copper 
of  these  weights,  with  muriatic  acid,  has  lost  each 
time  4  g  of  manganese : — 

«•  4  g,  c.  5.25  g, 

b.  2g,  d.  3.15  g, 


XVIII.— CHROMIUM. 

1.  What  is  the  percentage  composition  of  chromic  iron  ? 

2.  How  much  chromic  acid  (anhydric)  may  be  obtained 

from  chromic  oxide  as  follows : — 

a.  152  g,  c.   I  lb., 

b.  100  g,  d.  i  Kg? 

3.  What  quantity  of  di-chromate  of  potassium  may  be 

obtained  from  the  same  quantities  of  chromic  oxide 
by  melting  with  potassium  carbonate  and  saltpeter  ? 

4.  How  much  pure  chromic  iron  and  potassium  car- 
bonate must  be  taken  to  yield  potassium  di-chromate 
as  follows : — 

a.  294  g,  c.  100  Ibs., 

b.  131.25  Ibs.,  d.  i  Kg? 

5.  What  amount  of  di-chromate  of  potassium  and  sul- 

phuric acid   are   necessary  to  yield  chrome  alum 
as  follows : — 

a.  998  g,  b.   100  Ibs.,  c.  25  g? 

What  amount  of  water  will  be  taken  up  with  it  ? 


50  CHEMICAL   PROBLEMS. 

6.  What  is  the  amount  of  potassium   chromate,  that 

must  be  reduced   and   precipitated,  to   yield,  after 
heating — 

a.  152  g,  c.   100  g, 

b,  30  g,  d.   I  lb., 
of  chromic  oxide  ? 

7.  How  much  di-chromate  of  potassium,  sal-ammoniac, 
and  potassium  carbonate  must  be  heated  to  yield — 
a.   152  g,  b.  50  g,  c.   I  lb., 
chromic  oxide? 

8.  How  much  neutral   potassium   chromate  and   lead 

acetate  (Pb,C4H6O4  -j-  3  H2O)  are  necessary  to  ob- 
tain lead  chromate  as  follows  : — 

a.  323  g»  c-  50  g, 

b.  iclbs.,  d.  i  Kg? 

9.  What  per  cent,  chromic  acid  does  a  liquid  contain, 

20. 1 1   g  of  which  give  a  precipitate  of  barium  chro- 
mate weighing — 

a.  4.500  g,  b.   10.438  g? 

10.  What   quantity  of  sulphuric  acid   is    necessary   to 
convert — 

a.  194  g,  c.   10  g, 

b.  97  Ibs.,  d.  25  g, 

of  the  potassium  chromate  into  the  acid  salt  ? 


XIX.— ZINC. 

1.  What  per  cent,   should  a.  zinc-blende,   b.  calamine 

yield,  according  to  theory,  if  these  be  pure,  and 
there  is  no  loss  ? 

2.  How  many  cu  cm  of  zinc  (spec.  grav.  7.2)  must  be 
burned  to  obtain — 

a.  40.5  g,  b.  5.0625  g,  c.   10  g, 

of  zinc  oxide  ? 


CHEMICAL   PROBLEMS.  51 

3.  What  amount  of  zinc  must  be  dissolved  to  obtain, 

by  precipitating  with  carbonate  of  soda  and  heating 
the  precipitate,  zinc  oxide  as  follows  : — 

a.  40.5  g,  c-  5-0625  g, 

b.  10.125  Ibs.,  d.  10  g? 

4.  How  much  carbonate  of  soda  is  required  ? 

5.  What  quantity  of  white  vitriol  and  calcium  chloride 

must  be  distilled  to  obtain — 

a.  136  g,  b.  10  g,  c.  i  lb., 

of  zinc  chloride  ? 

6.  If  the  formula,  2  (ZnO,CO2)  +  3  (ZnO,H2O)  be  taken 

for  oxide  of  zinc,  how  many  cu  cm  are  necessary 
for  oxide  of  zinc  as  follows : — 

«•  547  g>  c.  10  g, 

b.  273.5  g,  d.  I  lb? 

7.  A  quantity  weighing  4.52  g  of  a  substance  contain- 

ing zinc  gave,  after  the  precipitation   of  the   zinc 
with  carbonate  of  soda,  and  heating  the  precipitate, 
1.71  g  of  zinc  oxide. 
What  per  cent,  of — 

a.  zinc, 

b.  "  oxide, 

c.  "  chloride, 

d.  "  sulphate, 

e.  "  carbonate, 
does  this  furnish  ? 


XX.— COPPER. 

1.  How  much  anhydrous  copper  nitrate  must  be  heated, 

to  obtain  cupric  oxide  as  follows : — 

a.  79.4  g,  c.   100  g, 

b.  39.7  Ibs.,  d.   10  Ibs.  ? 

2.  How  much  of  the  copper  nitrate  containing  3  H2O 
is  required  for  this  purpose  ? 


52  CHEMICAL   PROBLEMS. 

3.  What  quantity  of  the  last  mentioned  salt  must  be 

dissolved,  precipitated  with  alkali,  and  heated  to 
obtain  the  same  quantity  of  copper  oxide  ? 

4.  What  amounts  of  white  vitriol  and  carbonate  of  soda 

are  necessary  to  yield  cupric  oxide  as  follows  : — 

a.  79.4  g,  c.  100  g, 

b.  39.7  Ibs.,  d.  10  Ibs.  ? 

5.  How  much  copper  must  be  dissolved  by  nitric  acid 

to  obtain  cupric  oxide  as  follows,  after  the  pre- 
cipitation of  the  salt  obtained,  and  heating  of  the 
precipitate : — 

a.  79.4  g,  d.  62.6183  g, 

b.  39.7  g,  e.   12.5237  Ibs.? 

c.  125.2366  Ibs., 

6.  How  much  lighter  will  a  given  quantity  of  copper 

filings  become,  if  copper  oxide  be  formed  from  it  in 
weight  as  follows  : — 

*.  39.7  Ibs.,  c.   100  g, 

b.  125.237  g,  d.  5.01  g? 

7.  What   quantity   of    cupric    oxide    must   be    heated 

with — 

a.  63.4  g,  c.  5  Ibs., 

b.  10  g,  d.  50  g, 

of  copper  to  obtain  cuprous  oxide,  and  how  much 
of  the  last  will  be  formed  ? 

8.  How  many  cu  dm  of  oxygen  will  be  taken  up  by  a 
liquid  which  contains — 

a.  71.4  g,  b.  100  g,  c.  63.9744  g, 

of  cuprous  oxide  in  solution  ? 

9.  How  much   oxygen   can  be  absorbed  by  a   liquid 
which  contains  in  solution  the  cuprous  oxide,  origi- 
nating from  the  reduction  of — 

a.   1 59.4  g,  b.  223.25  g, 

of  copper  sulphate  ? 


CHEMICAL   PROBLEMS.  53 

10.  How  many  cu  dm  of  oxygen  will  be  absorbed  by 

copper  which  is  moistened  with — 

a.  196  g,  b.  274.5  g, 

of  sulphuric  acid,  containing  25  per  cent,  of  hy- 
drate? How  much  copper  will  be  dissolved  by 
this  operation? 

1 1.  How  much  copper  sulphate  will  be  obtained  from — 

a.  158.8  Ibs.,  c.   1000  Kg, 

b,  100  Ibs.,  ^.500  Ibs., 

cuprous  sulphide,  if  this  be  pure,  only  roasted  and 
lixiviated  with  water  ? 

12.  What    amount    may   be    obtained    if   the    roasted 

mass  be  lixiviated  with  water  containing  sulphuric 
acid? 

13.  What  per  cent,  of  crystallized  blue  vitriol  may  be 

obtained  from  an  ore  containing  7.5  per  cent,  cuprous 
sulphide,  with  no  losses  sustained  ? 

14.  How  much  copper  is  obtained  from — 

a.  1000  Ibs.,  c.  i  lb., 

b.  100  Kg,  d.  i  g, 
water-cement  which  contains  10.5  per  cent,  copper, 
copper  vitriol  ? 

15.  How  much  green  vitriol  will  crystallize  out  of  the 

liquid  obtained  by  the  precipitation  with  iron  ? 

1 6.  What  quantity  of  crystallized  blue  vitriol   may  be 

obtained  from  a  copper  ore  which  contains  7.5  per 
cent,  cuprous  sulphide,  if — 

a.  1000  Ibs.,  c.  5000  Kg, 

£.50  Kg,  d.  1000  cwt, 

be  employed  in  the  operation  ? 

17.  If  no  loss   is  sustained,  what  per  cent,  should  the 

following  pure  copper  ores  yield  : — 

a.  red  copper  ore,  d.  variegated, 

b.  black  copper,  e.  malachite, 

c.  chalcopyrite,  /.  azurite? 


54  CHEMICAL   PROBLEMS. 

1 8.  How  much  copper  is  obtained,  by  theory,  from — 

a.  100  Kg,  £  250  cwt, 

of    a   copper   ore   which    contains    2   per   cent,    of 
chalcopyrite  ? 

19.  What  is  yielded  by  theory  from  an  ore  as  follows, 

containing  25  per  cent,  malachite  : — 

a.  100  cwt.,  c.  200  cwt, 

b.  1000  Kg,  d.  1000  cwt.  ? 

20.  What  per  cent,  of  copper  do  alloys  contain,  of  which 

a.  2.1130  g,  c.  1.0025  g, 

b.  3.4004  g,  d.  2.2341  g, 

after  solution  and  precipitation  with  potassium  boil- 
ing hot,  gave  cupric  oxide  as  follows : — 

a.  1.8952  g,  c.  i. 0044  g, 
b-  3-5879  g>                             d.  2.51812  g? 

21.  What  per  cent,  crystallized  blue  vitriol  may  be  ob- 

tained from  a  water-cement,  of  which   150  Ibs.  have 
the  capacity  of  making  an  iron  bar  placed  into  it — 

*•  250  g,  b.  312.5  g, 

heavier  ? 

22.  When  an  iron  bar  has  become — 

a>  37  g,  c.  5  g, 

b.  0.37  g,  d.  14.8  g, 
heavier  by  lying   in  a  solution  containing  copper 
chloride,  the  increase  in  weight,  in  each  instance, 
indicates  the  quantity  of  chloride. 


XXI.— MERCURY. 

i.  How  much  mercuric  chloride  must  be  mixed  with 
mercury  to  yield  calomel  as  follows : — 

«•  47 i  g»  c-  3  Kg, 

b.  94.2  g,  ^.56  Ibs.  ? 


CHEMICAL    PROBLEMS.  55 

2.  What  quantity  of  mercuric  sulphate,  quicksilver,  and 
common  salt  must  be  sublimed  to  yield — 

a.  471  g,  c.  5  Ibs., 

b.  15.7  Ibs.,  d.  10  g, 
of  calomel  ? 

3    How  much  mercuric  sulphate  and  salt  must  be  sub- 
jected to  sublimation  in  order  to  obtain — 
a.   135.5  g,  b.  54-2  g,  c.   100  g, 

of  corrosive  sublimate? 

4.  How   much    quicksilver   must   be    dissolved,   when 
precipitated  as  oxide  and  dissolved  in  muriatic  acid, 
to  furnish  corrosive  sublimate  as  follows : — 

«•   135-5  g,  c-   I0  Kg> 

b.  4  Ibs.,  d.  TOO  g? 

5.  How  much  quicksilver  ore,  containing  24  per  cent. 

of  cinnabar,  must  be  consumed  to  get — 

a.  1 10  Ibs.,  c.  1000  Kg, 

b.  500  Ibs.,       .  d.  100  cwt, 
of  quicksilver? 

6.  By  the  analysis  of  three  liquids,  which  contain  differ- 

ent quantities  of  mercuric  chloride,  there  will  be 
obtained  from  every  10  g  of  the  same,  precipitated 
with  stannous  chloride — 

a.  0.5  g,  b.   1.1235  g,  c.   i. 4500  g, 

of  quicksilver.  What  amount  of  sublimate  does 
each  of  the  three  liquids  contain  ? 

7.  How  much  quicksilver  must  be  taken  with  an  excess 

of  nitric  acid  to  obtain — 

a.  17.28  g,  b.   100  g, 

crystallized  basic  mercuric  nitrate  ? 
Formulae  of  salt : — 

2  HgO,N205  +  2  H20. 
Or,  2  (NO3)  Hg,HgO  -f  2  H2O. 

8.  In  what  proportion  must  mercury  be  mixed  with 

iodine  to  obtain  mercuric  iodide  ? 


56  CHEMICAL   PROBLEMS. 

XXII.— LEAD. 

1.  How  much  lead  nitrate  must  be  heated  to  give — 

«•  223  g,  b.  100  g,  c.  5  Ibs., 

of  litharge  ? 

2.  What  amount  of  lead  must  be  oxydized  to  obtain 

the  same  quantities  ? 

3.  How  many  cu  dm  (i)  oxygen,  (2)  air  are  required 

for  this  oxydation?     (Vid.  IV,  5.) 

4.  What  amount  of  red  oxide  of  lead  is  necessary  to 

yield  plumbic  peroxide  as  follows,  if  this  be  taken 
as  the  formula  for  red  lead  Pb4O5 : — 

a-  239  g.  c.   13.3  g, 

b.  39.9  Ibs.,  d.   i  Ib.  ? 

5.  How  much  oxygen  is  absorbed  by  lead  oxide,  if  red 

lead,  corresponding  to  the  formula  Pb3O4,  be  formed 
as  follows : — 

a.  685  g,  c.  100  g, 

b.  137  Ibs.,  d.   i  Ib.? 

6.  What  amount  of  lead  must  be  worked  in  order  to 

produce  white  lead  as  follows  : — 

a.  775  Ibs.,  c.  1000  cwt., 

b.  100  Ibs.,  d.  10  Kg? 

7.  How  many  cu  m  of  carbonic  acid  are  needed  for  it  ? 

8.  How  much  plumbic  oxide  must  be  dissolved  in  the 
following  quantities  of  crystallized   neutral   acetate 
of  lead  to  obtain  basic  salts : — 

a.  379  Ibs.,  c.  25  g, 

b.  i  Ib.,  d.  189.5  g? 

9.  What   amount   of  lead    oxide  will   be  precipitated, 

by  means   of  carbonic   acid,  from  the   basic   salts 
obtained  in  (8)  ? 

10.  When  white  lead  is  to  be  obtained  from  a  given 
quantity  of  plumbic  oxide,  and  acetic  acid  only 
applied  once,  then  precipitated  with  carbonic  acid ; 
how  much  acetic  acid  is  necessary  ? 


CHEMICAL    PROBLEMS.  57 

11.  How  much  of  the  plumbic  oxide  is  obtained  in  the 
white  lead  ? 

12.  What  quantity  of  white  lead  may  be  obtained  by 

once  dissolving  and  precipitating  from — 

a.  1000  Kg,  b.  100  Ibs., 

of  plumbic  oxide  ? 

13.  How  much  plumbic  oxide  must  be  taken  under  the 
same  suppositions  to  yield  white  lead  as  follows : — 

a.  1550  Ibs.,  *.' 77-23  Kg, 

b.  772.3  Ibs.,  d.   1000  Kg? 

14.  When  there  is  no  loss,  what  per  cent,  of  lead  must 

the  following  ores  yield  : — 

a.  galena,  b.  cerusite,  c.  anglesite? 

15.  How  much  lead  ore,  containing  45  per  cent,  galena, 

is  necessary  to  produce  lead  as  follows  : — 

a.  i  lb.,  c.  100  Kg, 

b.  1000  Ibs.,  d.  4000  Kg? 

1 6.  What  per  cent,  of  lead  do  three  alloys  contain,  of 

which  every — 

1.5231  g,  2.0026  g,  4. 1 1 70  g, 

after  being  dissolved  in  nitric  acid,  give  precipitates 

with  sulphuric  acid  weighing — 

a.   1.4854  g,  b.   1.4658  g,  c.  4.2184  g? 


XXIII.— SILVER. 

1.  What  per  cent,  of  silver  does  silver  nitrate  contain? 

2.  How  much  pure  silver  must  be  dissolved  to  give 

silver  nitrate  as  follows  : — 

«•  340  g,  c.  5  g, 

b.  i  g,  d.  100  g? 

3.  How  much  silver  nitrate  may  be  obtained  from  three 

mark  pieces  when  the  same  together  weigh   16.7  g 
and  contain  90  per  cent,  of  silver  ? 
E 


58  CHEMICAL    PROBLEMS. 

4.  100  marks  may  be  coined  from  a  pound  of  silver, 
and  as  much  copper  added  as  to  make  the  compound 
0.900.     How  much  cupric  nitrate  (with  three  mole- 
cules of  H2O)  may  be  obtained  from  the  solution  of 
loo  marks?     How  much  lunar  caustic? 

5.  How  many  marks  are  dissolved  to  yield  caustic  as 

follows,   if  a   mark  weighs    5.556  g  and   has    fine 

quality  of  0.900 : — 

a.   100  g,  b.   I  lb.,  c.  78.71  g? 

6.  What  amount  of  a.  HC1,  b.  barium  chloride,  c,  sodium 

chloride  is  contained  in  a  liquid  from  which  silver 
solutions  give  a  precipitate  weighing  3.59  g? 

7.  What  per  cent,  of  chlorine  do  two  substances  contain 

of  which — 

a.  2. 1 340  g,  b.  34203  g, 

give  a  precipitate  of  silver  chloride  weighing 
1.19667  g? 

8.  How  much  must  the  precipitates  weigh  which  give 

pure  sodium  chloride  as  follows,  with  a  silver  solu- 
tion : — 

a.  5.2401  g,  b.  2.0301  g? 

9.  What  per  cent,   of  pure  silver  is   contained  in  an 

alloy,  of  which  2.505  g,  with  a  solution  of  common 
salt,  give  a  precipitate  amounting  to  2.66272  g  ? 

10.  How  much  plumbic  oxide   can   be  obtained   from 

1000  Ibs.  of  lead  which  contains  0.5  g  of  silver  to 
the  pound  ? 

11.  How  much  gold,  silver,  and  crystallized  blue  vitriol 

may  be  obtained  by  the  refining  of  1500  g  of  silver 
which  contains  -^^  gold  and  -f^  silver?  How 
much  copper  will  be  consumed  by  this  operation  ? 

12.  What  amount  of  gold,  silver,  and  blue  vitriol  may 

be  obtained  by  the  refining  of  old  silver  coins  in 
quantities  of — 

a.  i50g,  b.  200  Kg,  c.  30  g? 

The  gold  amounts  to  0.002,  the  silver  to  0.9.  How 
much  copper  will  be  consumed  ? 


CHEMICAL    PROBLEMS.  59 

13.  If  a  copper  sheathing  is  laid  in  a  solution  of  silver, 

after  separation  of  the  silver  precipitated  thereon 
it  has  become — 

«•  634  g,  c.  5  g, 

b.  10  g,  <£  2.5  g, 

lighter;  how  much  silver  nitrate  was  then  contained 

in  the  solution  ? 

14.  Copper  sheathing  is    laid    in   different  solutions   of 

silver  chloride  and  common  salt.  After  the  pre- 
cipitation of  all  the  silver,  the  sheathings,  with  the 
silver  precipitates,  weigh — 

a.  15.26  g,  c.   1.09  g, 

b.  0.763  g,  d.  2.i8g, 

more  than  before.  How  much  silver  chloride  does 
each  of  the  four  solutions  contain  ? 


XXIV.— TIN. 

1.  How   much   tin   and    HC1    are    required    to   yield 

stannous  chloride  as  follows  : — 

a.  225  Ibs.,  d.  100  g, 

b.  75  Kg,  e.  loo  Ibs.? 
'•  5  g, 

2.  How  much  of  a  muriatic  acid  containing  %  of  the 

acid  is  needed  for  the  same  purposes  ? 

3.  How  many  cu  dm  of  chlorine  must  be  conducted  over 
tin  as  follows,  to  convert  the  same  into  stannic  chlo- 
ride : — 

a.   118  g,  c.  5.9  g, 

b-  2.95  g,  d.  5  g? 

4.  From    how  much   black    oxide   of  manganese  and 

HC1  must  the  chlorine  be  evolved  to  change — 
a.   Ii8g,  c.  5.9  g, 

b-  2-95  g,  d.  5  g, 

of  tin  to  stannic  chloride  ? 


60  CHEMICAL    PROBLEMS. 

5.  How  much  tin  ore,  containing  9  per  cent,  tinstone, 

is  required  to  yield — 

a.   100  Ibs.,  b.  1000  cwt,  £.500  Kg, 

of  tin  ? 

6.  What  per  cent,  of  tin  do  two  alloys  contain  of  which — 

a.  3.02  g,  b.  2.5016  g, 

by  treating  with  nitric  acid,  after  heating,  give — 

a.   1.9198  g,  b.  0.795  g, 

of  a  residue  ? 

7.  The   tin  is  precipitated  as   sulphide   from  a   liquid 

amounting  to  26.54  g  and  this  is  converted  by 
roasting  into  oxide.  4.3978  g  are  obtained  from 
this.  What  per  cent,  of  stannous  chloride  does  this 
liquid  contain  ? 


XXV.— ANTIMONY. 

1.  What  per  cent,  of  antimony  do  two  alloys  contain 

of  which   every   2.5402   g,   by  treating  with   nitric 
acid,  give — 

a.  0.797  g,  b.  0.836  g, 

of  antimonic  acid  ? 

2.  How  much  antimonous  sulphide  is  employed  in  the 

operation  to  obtain,  by  heating  with  sodium  and 
sulphur,  first  sodium  sulph-antimonate  (Schlippe's 
salts,  SbS4Na3  +  9  H2O),  and  then,  by  the  addition 
-  of  an  acid,  the  following  quantities  of  antimonic  sul- 
phide : — 

a.  404  g,  c.  i  o.i  Ibs., 

b.  50.5  g,  d.   i  g? 

3.  What  quantity  of  antimonous  chloride  and  sodium 

carbonate  are  required  to  yield — 

a.  292  g,  b.   14.6  g,  c.   i  lb., 

of   antimonic  oxide?     What  bye-products   will  be 

obtained,  and  how  much  ? 


CHEMICAL   PROBLEMS.  61 

How  much  Schlippe's  salt  (Vid.  2.)  and  muriatic 
acid  of  20  per  cent,  of  contents  are  necessary  to 
yield  golden  sulphuret  (Mosaic  gold)  as  follows  : — 

a.  404  g,  c.   i  g, 

b.  i  o.i  Ibs.,  d.  100  g? 

What  amount  of  sulphuric  acid  instead  of  the 
muriatic  is  used,  if  it  still  contains  ]/2  molecular 
weight  of  water,  in  addition  to  its  water  of  hydra- 
tion  ? 

What  per  cent,  of  antimony  must  be  obtained  by 
theory  from  the  melted  gray  antimony  ? 

In  what  proportion  must  iron  and  the  sulphide  of 
antimony  be  heated  together  in  obtaining  antimony  ? 


XXVI.— ARSENIC. 

1.  How  much  sulphur   and   arsenic   must  be  melted 

together  to  obtain — 

a.  214  g,  c.   100  Ibs., 

b.  107  Ibs.,  d.   i  Kg, 
red  sulphur  of  arsenic  (Realgar)  ? 

2.  How  much  sulphur  must  be  melted  with  arsenic  to 

obtain  yellow  arsenic  as  follows  : — 

a.  246  g,  c.  41  g, 

b.  123  Ibs.,  d.   i  Kg? 

3.  What  amount  of  arsenious  acid  do  four  liquids  con- 

tain from  which  the  following  amounts  of  arsenic 
sulphide  may  be  precipitated  by  means  of  hydrogen 
sulphide  : — 

a.  1.23  g,  .c.  2.46  g, 

b.  4-1  g,  d.  3.011  g? 


62  CHEMICAL    PROBLEMS. 

4.  What  per  cent,  of  arsenic  do  three  substances  con- 
tain of  which  every  5.214  g  give  a  precipitate,  after 
solution  and  precipitation  with  hydrogen  sulphide 
of— 

a.  0.3211  g,  b.  0.0045  g>  c-  0-0555  g> 

arsenic  sulphide  ? 


XXVII.— PLATINUM. 

1.  From  a  substance  containing  ammonia,  a  precipitate 

was  obtained  by  platinum  chloride  and  the  platinic 
sal-ammoniac  obtained  was  heated ;  2.2  g  of  the 
substance  were  taken  ;  the  residual  platinum  weighed 
3.29  g.  How  much  ammonium  oxide  may  be  calcu- 
lated from  this  ? 

2.  If  precipitates  were  obtained  from  two  liquids  with 

platinic  chloride,  which  yielded  by  heating — 
a.  0.47  g,  b.  7.1022  g, 

of  platinum,  how  much  sal-ammoniac  was  contained 
in  the  liquids  ? 

3.  If  you  have  4  g  of  platinum  ore  containing  90  per 

cent,  platinum,  how  much  a.  ammonium  oxide, 
b.  potassium,  can  be  precipitated  by  the  platinic 
chloride  that  can  be  made  from  this  ? 

4.  By  an  organic  analysis  the  nitrogen  of  the  substance 

amounting  to  2.1234  g  may  be  converted  into  am- 
monia, this  united  with  muriatic  acid  and  then 
precipitated  with  platinic  chloride.  The  platinum 
obtained  by  heating  the  precipitate  weighs  2.0412  g. 
What  per  cent,  of  nitrogen  does  the  organic  sub- 
stance contain  ? 


PART  SECOND. 


XXVIII.— APPROXIMATE    RATIOS. 

The  correct  approximate  proportions  of  necessary  ma- 
terials are  to  be  computed  in  the  following  ex- 
amples : — 

1.  Preparation   of  hydrogen  from   zinc  and   sulphuric 

acid. 

Solution ;  Original  relation  65  :  98.     Since  this  ratio  did  not  admit 
of  simplification,  I  was  added  to  the   first  term  and  it 
stood  66  :  98  or  33  :  49.     Each  term  was  now  diminished 
by  I,  so  that  it  would  stand  32  :  48  or  2  :  3. 
Proof:  65  :  97.5. 

2.  Preparation    of  chlorine   from    manganese   di-oxide 

and  HC1. 

3.  Preparation  of  oxygen  by  means  of  black  oxide  of 

manganese  and  sulphuric  acid. 

4.  Preparation  of  chlorine  from  manganese  di-oxide  and 

muriatic  acid  containing  41.858  per  cent. 

5.  Preparation    of  caustic  potash.      Relation    of  burnt 

lime  to  potassium  carbonate. 

6.  Preparation   of  soda  from   crystallized   sodium   sul- 

phate, etc. 

7.  Preparation  of  ammonia  from  sal-ammoniac  and  un- 

slaked lime. 

8.  Preparation  of  barium   carbonate  from  barium  sul- 

phate and  potassium  carbonate. 

9.  Preparation  of  nitric  acid  from  powdered  saltpeter, 
and  a   sulphuric  acid   containing    13.531    per  cent, 
excess  of  water. 

10.  Preparation  of  potassium  chlorate  by  means  of  potas- 

sic  hydrate,  black  oxide  of  manganese,  and  HC1. 

63 


64  CHEMICAL   PROBLEMS. 

XXIX.-TEMPERATURE  AND  ATMOSPHERIC 

PRESSURE. 

\ 

1.  How  many  cu  m  of  oxygen  may  be  obtained  from 

I  Kg  of  potassium  chlorate,  if  the  gas  be  measured 
at  a  temperature  of  18°  C.  ? 

2.  What  volume  in   cu   cm  would  the  explosive  gas 

evolved  from  I  cu  cm  of  H2O  occupy  when  ignited, 
if  it  be  free  to  expand,  and  it  be  granted  that  the 
coefficient  of  expansion  be  constant,  and  the  tem- 
perature of  the  ignited  gas  amount  to  12,000°  C.  ? 

3.  If  water  absorbs  600  times  its  volume  of  ammonia 

gas,  what  is  then  the  volume  of  the  gas  at  120°  C., 
which  has  been  taken  up  by  ten  pounds  of  water  ? 

4.  How  much  is  the  volume  of  carbonic  acid,  at  15° 
and  750  mm  pressure,  which  can  be  evolved  from 
4  Kg  480  g  calcium  carbonate  ? 

5.  What  is  the  relation  between  the  volume  of  air  that 

must  be  mixed  with  the  sulphurous  acid  arising 
from  10  g  of  sulphur,  in  order  to  yield  the  oxygen 
necessary  for  the  formation  of  sulphuric  acid  and 
that  of  the  sulphurous  acid  itself?  The  gases  are 
to  be  compared  at  748  mm,  and  12°  for  the  air,  and 
120°  for  the  sulphurous  acid.  (Oxygen  =  0.21  of 

,-       air-) 

6.  By  an  organic  analysis  1.0152  g  of  a  substance  gave 

40.72  cu  cm  of  nitrogen,  measured  at  12°  and  730 
mm  pressure.  What  per  cent,  of  nitrogen  does  the 
substance  contain? 

7.  What  amount  of  calcium   carbonate  would  be   re- 

quired for  73.24  cu  m  of  carbonic  acid,  measured  at 
730  mm  pressure  and  100°  C.  ? 

8.  When  water  at  o°  and  760  mm  pressure  absorbs  33 
times  its  volume  of  sulphurous  acid,  the  volume   of 
this   gas   is  to  be  calculated,  which  5  Kg  of  water 
can  take  up,  if  the  gas  in  the  apparatus  has  a  medium 
temperature  of  82.8°  C.,  and  the  liquid  columns  of 
the  apparatus,  with  a  barometric  height  of  758  mm, 


CHEMICAL   PROBLEMS.  65 

exert  a  pressure  equal  to  that  of  5  mm  of  mercury. 
No  account  is  taken  of  the  expansion  of  the  water 
which  takes  place  at  10°. 


XXX.— MIXED    PROBLEMS. 

1 .  How  long  will  a  Dobereiner  lamp  continue  in  opera- 
tion before  (i)  the  sulphuric  acid,  (2)  the  zinc  must 
be  renewed,  if  the  same  be  supplied  with  135.926  g 
of  sulphuric  acid,  and  90.155  g  of  zinc;  and  if  86 
cu  cm  of  hydrogen  be  consumed  daily? 

2.  What  is  the  answer  for  the  above  if  200.9  g  °f  su^~ 

phuric  acid  be  taken  and  139.776  g  of  zinc,  and  if 
100  cu  cm  of  hydrogen  be  consumed  daily? 

3.  How  much  zinc,  sulphuric  acid,  and  potassium  chlo- 

rate are  required  for  two  -  hours'  exhibition  of  the 
Drummond  light,  if  there  is  an  average  consumption 
per  minute  of  324  cu  cm  of  oxy-hydrogen  gas? 

4.  It  is  required  to   saturate  3300  Ibs.  of  water  with 

COa.  It  is  accomplished  by  a  pump  with  a  force  of 
6  atmospheres.  How  much  sulphuric  acid  with  ^ 
the  molecular  weight  of  water,  in  addition  to  its 
hydrate,  and  how  much  (pure)  marble  are  neces- 
sary ? 

5.  It  is  required  to  obtain  509  Kg  856  g  of  water  con- 

taining CO2,  and  the  carbonic  acid  pressed  in  with 
10  atmospheres.  How  much  water,  calcium  car- 
bonate, and  sulphuric  acid  are  needed  ? 

6.  In  determining  the  CO2  in  gases,  making  two  esti- 

mations daily,  50  cu  cm  of  gas  are  used  in  each 
determination.  Of  this  volume,  20  per  cent,  at  the 
highest  were  found  to  be  CO2;  i.  e.y  the  amount 
absorbed  by  caustic  potash,  which,  too,  must  be 
employed  here  in  the  least  possible  quantity.  How 
much  potassium  hydrate  would  be  consumed  annu- 
ally? 


66  CHEMICAL    PROBLEMS. 

7.  Under  like  conditions,  as  those  of  Prob.  6,  we  are  to 

calculate  what  must  be  the  least  length  of  a  cylin- 
drical piece  of  fused  potash  employed.  100  cu  cm  of 
gas  are  tested  each  time,  of  which,  on  an  average  */5 
is  absorbed.  Owing  to  the  wrater  contained  in  the 
potash  y±  more  than  the  necessary  amount  of  it  is 
taken.  The  diam.  of  the  stick  is  6  mm,  spec.  grav. 
2.1. 

8.  It  is  desired  to  obtain  4  Kg  15.232  g  of  H2O  satu- 

rated with  H2S.  The  water  takes  up  2.5  times  its 
volume  of  this  gas.  How  many  liters  of  H2O,  how 
many  grams  of  sulphuric  acid,  and  how  much  sul- 
phide of  iron  are  necessary  ? 

9.  How  many  liters  of  water,  Kg  sulphide  of  iron  and 
sulphuric   acid  are   necessary  to   yield    10   Kg  of 
hydrogen  sulphide  water? 

10.  What  per  cent,  of  foreign  substance  does  a  diamond 

contain,  of  which,  0.0145  g  gave  as  much  gas  in 
burning  as  would,  with  lime  water,  give  a  precipitate 
amounting  to  0.12  g? 

1 1.  What  quantity  of  calcium  carbonate  must  you  obtain 

by  the  absorption  of  the  carbonic  acid  originating 
from  the  burning  of  0.0063  g  of  diamond  ? 

12.  As  the  gas  originating  from  the  burning  of  a  diamond 

of  unknown  weight  is  collected  with  the  surplus 
oxygen  over  mercury,  the  volume  of  the  obtained 
gas  was  diminished  5.52  cu  cm  by  adding  caustic 
potash.  (Reckoned  with  normal  temperature  and 
normal  pressure).  What  did  the  consumed  part  of 
the  diamond  weigh  ? 

13.  loo  g  of  pure  potassium  carbonate  are  obtained  by 
the  heating  of  potassium  acetate.    The  latter  should 
be  obtained  by  means  of  neutral  lead  acetate.    What 
must  be  done  ? 

14.  What  per  cent,   of  hydrochloric  acid    gas    must  a 

commercial  muriatic  acid  contain,  of  which  6  g 
exactly  suffice  to  dissolve  \y2  g  of  pure  calcium 
carbonate  ? 


CHEMICAL   PROBLEMS.  67 

15.  What  per  cent,  of  hydrochloric  acid  gas  does  com- 

mercial muriatic  contain,  of  which,  1 5  g  are  needed 
to  neutralize  10.245  g  of  a  potassium  solution  which 
contains  48  per  cent,  of  hydrate  ? 

1 6.  For  the   determination   of  chlorine  by  means   of  a 

tenth  silver  solution  (TV  AgNO3  in  grams  dissolved 
1000  cu  cm  water)  300  cu  cm  of  water  were  used 
and  the  final  reaction  reached,  after  the  consump- 
tion of  0.55  cu  cm.  How  much  a.  chlorine,  b.  sodium 
chloride  does  the  water  contain  in  1000  parts? 

17.  25  cu  cm  of  water  served  for  the  determination  of 

nitric  acid  by  means  of  titrated  indigo  solution. 
This  was  standardized  so  that  6.5  cu  cm  were  equal 
to  o.ooi  g  of  nitric  acid.  The  blueing  set  in  after 
2.2  cu  cm  of  the  indigo  solution  were  added.  How 
much  nitric  acid  is  contained  in  1000  parts  water? 

1 8.  For  the  determination  of  the  lime   contained  in  a 

limestone,  it  can  be  dissolved  in  muriatic  acid,  the 
lime  precipitated  as  oxalate,  the  precipitate  dissolved 
in  dilute  sulphuric  acid,  and  the  oxalic  acid  in  the 
solution  determined  by  a  standard  solution  of  per- 
manganate of  potash  in  water.  The  latter  is  so  stand- 
ardized that  I  cu  cm  of  the  same  corresponds  to 
0.0063  g  of  oxalic  acid  (i.  e.,  jJw  C2H6O6).  By  I  g 
of  limestone  one  liter  was  obtained ;  and  for  100 
cu  cm  of  this,  18.2  cu  cm  of  the  permanganate  solu- 
tion were  required. 

What   per   cent,    of   calcium    carbonate    did   the 
limestone  contain? 

19.  100  cu  cm  of  an  alkaline  liquid  of  1.102  spec.  grav. 
should  be  mixed  with  normal  nitric  acid  (T1JV<y  HNO3) 
till  the  alkali  reaction  disappears  and  5.3  cu  cm  are 
consumed  for  this.     What  will  be  the  percentage, 
computed  by  this  means,  of — 

a.  lime  (calcium  oxide), 

b.  potassium  (potassium  oxide), 

c.  ammonia  (NH8)  ? 


68  CHEMICAL   PROBLEMS. 

20.  100  cu  cm  of  a  liquid,  which  contained  free  acid  and 
possessed  a  spec.  grav.  of  I .  I  were  titrated  with  nor- 
mal soda  (T^T  NaOH)  and  consumed  6.1  cu  cm  of 
this. 

What  is  the  percentage,  computed  by  this  means, 
of— 

a.  sulphuric  anhydride, 

b.  nitric  anhydride, 

c.  hydrochloric  acid? 

21  •  5-3  S  °f  calcined  soda  were  dissolved  in  water  and 
supersaturated  with  100  cu  cm  of  normal  sulphuric 
acid  (I^VTT  H2SO4).  After  the  expulsion  of  the  car- 
bonic acid  by  boiling,  it  was  colored  with  litmus 
and  retitrated  with  barium  hydrate.  By  this  means 
45.6  cu  cm  of  the  latter  were  consumed,  while  a 
preceding  experiment  has  shown  that  10  cu  cm  of 
a  normal  sulphuric  acid  would  exactly  neutralize 
66.6  cu  cm  of  the  barium  solution.  What  per  cent, 
of  sodium  carbonate  did  the  calcined  soda  contain  ? 

22.  By  the  analysis  of  a  bone  charcoal,  100  Ibs.  of  the 

same  were  found  to  yield — 

10.2  Ibs.  of  calcium  carbonate, 

63.2  Ibs.  of        "        phosphate. 

What  per  cent,  of  the  weight  of  this  bone  charcoal, 
in  sulphuric  acid  of  60  per  cent.,  is  exactly  neces- 
sary for  the  decomposition  ? 

23.  A  stick  of  marble  weighed   log;  it  was  placed  in 

vinegar  which,  with  a  spec.  grav.  1.0334  occupied  a 
volume  of  15  cu  cm.  After  the  evolution  of  gas 
had  ceased,  the  stick  of  marble  still  weighed  8.698  g. 
What  per  cent,  of  acetic  acid  (C2H4O2)  did  the 
vinegar  contain?  (i  molecule  of  calcium  carbonate 
requires  2  molecules  of  acetic  acid  for  saturation.) 

24.  What  weight  is  able  to  keep  up  a  spherical  air  balloon 

in  equilibrium,  which  has  a  diam.  of  4  m,  is  filled 
with  hydrogen,  and  the  covering  of  it  weighs  5.31 
Kg?  Temperature  o°  and  normal  pressure  are 


CHEMICAL   PROBLEMS.  69 

taken,  and  the  spec.  grav.  of  the  air  =  14  times 
that  of  hydrogen. 

25.  In  a  known  quantity  of  ashes  are  62.7  g  of  potassium 

and  sodium.  Both  oxides  were  converted  into  sul- 
phates, and  of  this  122.8223  g  obtained.  What  per 
cent,  of  potassium  and  sodium  did  that  quantity  of 
ashes  contain  ? 

26.  In  a  quantity  of  silicate  amounting  to  5.2  g,  1.9  g  of 

potassium  and  sodium  are  found.  From  this  the 
sulphuric  acid  salts  are  produced,  and  of  these, 
3.7182  g  obtained.  What  per  cent,  of  potassium 
and  sodium  does  the  silicate  contain  ? 

27.  A  substance  weighs   10.4  g.     The  quantity  of  potas- 

sium and  sodium  contained  in  it  amounts  to  1.9  g. 
From  this  3.7182  g  sulphates  were  obtained.  What 
per  cent,  of  potassium  and  sodium  carbonate  may 
be  obtained  from  these  for  that  substance  ? 

28.  In  what  relation  must  the  price  of  the  pure  caustic 

potash  stand  to  that  of  the  pure  caustic  soda,  if,  as 
regards  the  cost  of  the  articles,  it  is  immaterial 
which  of  the  two  should  be  used  ? 

29.  How  must  the  price  of  potassium  carbonate  propor- 

tion itself  to  that  of  the  crystallized  sodium  carbon- 
ate, if  the  advantage  shall  arise  from  the  employment 
of  the  latter  ? 

30.  In  a  large  laboratory,  where  the  necessary  caustic 

potash  is  made  from  the  carbonate,  there  is  an 
average  annual  consumption  of  60  Ibs.  pure  carbon- 
ate. The  question  arises,  what  advantage  will  there 
be  in  the  use  of  carbonate  of  sodium  ?  The  price 
of  the  first  is  50  cts. ;  that  of  the  latter  (crystallized) 
15  cts.  a  kilo. 

31.  How  many  cu  dm  of  copper  may  be  obtained  by 

laying  154.579  cu  dm  of  iron,  spec.  grav.  7.6,  in  a 
blue  vitriol  solution  containing  20  per  cent,  of  an- 
hydrous salts,  if  it  be  granted  that  the  separated 
copper  will  be  re-melted  and  have  a  spec.  grav.  of 


70  CHEMICAL    PROBLEMS. 

8.7  ?  How  many  pounds  of  the  original  solution 
were  decomposed  for  this  ? 

32.  What  does  a  pound  of  lunar  caustic  cost,  if,  in  its 

production,  a  25  ct.  piece  of  silver  and  an  acid  of 
45  per  cent,  anhydride  (price  25  cts.  a  kilo)  are 
used  ?  The  additional  expenses  are  regarded  as 
covered  by  the  obtained  copper.  (The  weight  and 
the  quantity  of  the  25  ct.  piece,  see  silver  XXIII,  5.) 

33.  How  much  silver  in  an  alloy,  of  which   1 19.904  g, 

treated  with  nitric  acid,  give  157.4  g  of  lunar  caustic? 

34.  How  much  manganese  di-oxide  is  necessary  to  yield 

i  cwt.  of  potassium  chlorate,  if  it  be  granted  that 
35  per  cent,  of  the  chlorine  is  lost  in  the  operation  ? 

35.  How  much  carbonic   acid   may  be    obtained   from 

no  Ibs.  of  limestone,  which  contains  31  per  cent, 
gangue  ? 

What  quantity  of  sulphuric  acid  is  required  for 
this? 

36.  What  amount  of — 

a.  hydrochloric  acid, 

b.  muriatic  acid  55  per  cent,  of  H2O 
are  necessary  for  this  ? 

37.  What  amount  of  carbonic  acid  maybe  obtained  from 

25  Kg  of  a  limestone,  which  contains  30  per  cent, 
of  magnesium  carbonate? 

38.  How  much  common  salt  with  3  per  cent,  of  mag- 

nesia sulphate,  is  necessary  to  obtain  1 10  Ibs.  of 
muriatic  acid  containing  28  per  cent,  hydrochloric 
acid  gas,  and  how  much  sulphuric  acid  containing  4 
per  cent,  surplus  water  is  employed  for  this  ? 

39.  What  per  cent,  of  hydrochloric  acid  will  a  nitric  acid 

contain  which  is  made  from  potassium  nitrate  that 
contains  12  per  cent,  of  sodium  chloride?  The 
calculation  must  be  made  with  the  hydrate  HNO3. 

40.  How  much  sulphuric  acid  is  necessary,  with  45  Kg 

of  this  saltpeter? 


CHEMICAL    PROBLEMS.  71 

41.  How  much   H2O  must  t>e  employed  in  the  manu- 

facture of  100  Ibs.  of  nitric  acid,  if  the  acid  to  be 
obtained  shall  contain  32  per  cent,  of  H2O,  and  the 
sulphuric  acid  be  mixed  with  so  much  H2O  that  it 
will  contain  8  per  cent.  H2O  in  addition  to  the 
hydrate  ? 

42.  How  much  saltpeter  with  7.5  per  cent,  common  salt, 

and  how  much  sulphuric  acid  with  8  per  cent,  foreign 
materials  are  necessary,  not  acting  in  the  decomposi- 
tion, to  yield  1000  Ibs.  of  an  aquafortis  containing 
1 8  per  cent,  of  the  contents  of  anhydrate  ? 

43.  We   have   solid    nitrogenous    substances   containing 

1 5  per  cent,  of  nitrogen,  and  these  are  mixed  with 
half  their  weight  of  liquid  nitrogenous  substances 
containing  2  per  cent  of  nitrogen.  It  is  required  to 
obtain  saltpeter  from  this ;  the  question  becomes, 
a.  What  is  the  least  amount  of  lime  (CaO)  that  must 
be  mixed  with  1000  Kg  of  the  mixture,  and  how 
much  potassium  carbonate  is  needed  to  convert  the 
obtained  lime  into  potassium  nitrate  ?  b.  How  much 
potassium  nitrate  will  be  obtained  if  it  be  granted 
that  22  per  cent,  of  nitrogen  is  lost? 

44.  How  much  zinc  containing  5.712  per  cent,  of  lead, 

and  sulphuric  acid  containing  20  per  cent.  H2O 
(besides  the  hydrate)  are  necessary  to  yield  11.16 
cu  dm  hydrogen  ? 

45.  How  would  the  requirements  of  the  preceding  ex- 
ample stand  if  muriatic  acid  containing  23  per  cent, 
of  hydrochloric  acid  should  be  employed  ? 

46.  A  vitriol  which  may  contain  2  parts  green  vitriol, 

3  parts  blue  vitriol,  and  besides  this  still  12  per  cent, 
of  the  whole  weight  of  foreign  materials  shall  be 
employed  for  obtaining  cementation  copper.  How 
much  of  this  and  how  much  iron  containing  2^  per 
cent,  of  a  carbonate  are  to  be  taken  to  yield  100  g 
of  copper? 

47.  1000  Kg  of  very  concentrated   Nordhausen  vitriol 


72  CHEMICAL    PROBLEMS. 

are  to  be  obtained,-  which  may  contain  in  the  whole 
9  per  cent,  of  H2O.  How  much  English  sulphuric 
acid  with  6  per  cent,  of  H2O  besides  the  hydrate  is 
necessary  to  take  up  the  sulphuric  acid,  and  how 
much  sulphur  residue  (Fe7S8)  must  be  roasted  when 
the  green  vitriol  is  de-hydrated  and  converted  into 
basic  ferric  sulphate  ? 

48.  Calculate  the  quantities  of  raw  material,  according  to 

theory,  necessary  to  yield  1000  Kg  cf  ferro-cyanide 
of  potash.  A  mixture  of  nitrogenous  substances 
must  be  used  which  contains,  on  an  average,  12.5 
per  cent,  of  nitrogen,  0.75  per  cent,  iron,  and  2^ 
per  cent,  potassium  carbonate.  The  added  potash 
has  8  per  cent,  of  impurities. 

49.  With  how  much  manganese  di-oxide,  containing  22 

per  cent,  of  foreign  matter,  is  one  able  to  evolve  the 
most  chlorine  in  order  to  obtain  nitrogen  by  con- 
ducting it  through  64  g  of  an  ammonium  solution, 
which  may  contain  18  per  cent,  of  ammonium  oxide, 
without  forming  nitrogen  chloride  ? 

50.  Wanted,  the  quantities  of  sulphuric  acid  and  carbon 

which  exactly  suffice  to  yield  10.64  cu  dm  of  sul- 
phurous acid ;  the  sulphuric  acid  contains  3  per  cent, 
salts,  and  of  liquid  parts  still  4.124  per  cent,  of  H2O 
(besides  the  hydrate);  the  carbon  contains  7.5  per 
cent,  of  salts. 

5 1.  A  limestone  contains  6.5  per  cent,  silicic  acid.    What 

portion  is  dead  burnt  by  too  high  heat  ?  What  per 
cent,  of  H2O  is  required  for  the  slaking  of  this  lime — 

a.  if  it  be  well  burnt, 

b.  when  it  is  dead  burnt  ? 

It  is  granted,  that  in  the  resulting  silicate,  the  oxygen 
of  the  silicic  acid  bears  the  ratio  to  the  base  3:1. 

52.  What  is  the  percentage  composition  of  gunpowder 

if  it  be  granted  that  the  charcoal  contains  just  92 
per  cent.  C,  the  saltpetre  0.15  per  cent,  the  sulphur 
1.05  per  cent,  of  impurities? 


CMEMICAL   PROBLEMS.  73 

53.  What  amount  of  lead  oxide  and  calcium  carbonate 

and  sulphuric  acid  are  necessary  to  obtain  I  Ib.  of 
white  lead,  if  it  is  only  desired  to  make  sugar  of 
lead,  and  we  do  not  wish  to  dissolve  the  lead  oxide 
more  than  once  in  it ;  and  if  it  be  granted  that  the 
neutral  salt  was  precipitated  ? 

54.  The  copper  is  to   be  obtained  from   2  Ibs.  copper 

sulphide  and  may  be  done:  (i)  by  roasting,  dissolv- 
ing, and  precipitating  with  iron ;  (2)  by  roasting, 
dissolving,  and  precipitating  with  potassium,  heating 
and  reducing  the  oxide  with  hydrogen.  The  ques- 
tion is  now — 
(For  i).  a.  How  much  copper  may  be  obtained? 

b.  How  much  iron  is  used  ? 

c.  How  much  crystallized  green  vitriol  may 

be  obtained  ? 

(For  2).  How  much  zinc  is  consumed  to  yield  the 
necessary  amount  of  hydrogen  ? 

55.  How  much  barium  sulphide  and  sodium  carbonate 

are  necessary  to  produce  the  quantity  of  barium 
carbonate,  which,  decomposed  by  acetic  acid,  ex- 
actly suffices  to  convert  3.54  g  of  potassium  sulphate 
into  acetate,  and  how  much  potassium  carbonate  will 
be  obtained  if  this  be  heated  ? 

56.  How  much  mercuric  sulphide  must  be  distilled  with 

lime  to  obtain  that  quantity  of  mercury  which,  after 
its  oxidation  with  nitric  acid  and  conversion  into 
oxide,  is  exactly  sufficient  to  furnish  5.33  g  of  oxy- 
gen ? 

57.  A  soda  manufactory  is  combined  with  a  manufactory 

of  English  sulphuric  acid,  which  shall  exactly  cover 
the  consumption  of  the  soda  manufactory.  In  the 
latter  1000  cwt.  of  crystallized  soda  are  produced 
monthly.  What  is  the  monthly  consumption  of 
iron  pyrites  for  the  sulphuric  acid,  if  sulphur  is 
first  obtained  from  the  same  and  this  shall  then 
be  burnt  ? 


74  CHEMICAL   PROBLEMS. 

58.  How  much  chrome-iron  must  be  employed  in  the 

operation  to  obtain  exactly  the  necessary  quantity 
of  neutral  potassium  chromate  which  is  necessary 
to  furnish  20  Kg  of  lead  chromate  ? 

59.  It  is  required  to  furnish   100  g  of  assay-lead  from 

red-lead.  This  is  treated  with  nitric  acid,  the  ob- 
tained salts  heated,  the  oxide  dissolved  in  acetic 
acid  and  zinc  suspended  in  the  solution.  How  much 
red-lead  must  be  employed  in  the  operation  ?  The 
red-lead  is  taken  as  Pb4O5. 

60.  Calomel  is  to  be  furnished  from  a  quantity  of  mer- 

cury amounting  to  40  g.  The  mercuric  nitrate  is 
precipitated  with  potassium,  the  oxide  dissolved  by 
sulphuric  acid,  and  then  proceed  according  to  XXL, 
2.  How  much  calomel  can  be  obtained,  and  is  the 
whole  amount  of  mercury  dissolved  in  nitric1  acid, 
or  what  portion  of  it  ? 

61.  It  is  desired  to  obtain  168.5  S  °f  chromic  oxide,  and 

for  this  di-potassium  chromate  is  employed.  The 
question  is,  how  much  of  it  is  to  be  treated  with 
sulphuric  acid  and  alcohol  ? 

62.  How  much  cryolite  is  required  to  yield  1000  Kg  of 
soda,  if  a  loss  of  5.51  per  cent,  is  sustained? 

63.  How  much  alum  will  be  obtained  as  bye-product,  if 

the  same,  not  pure,  be  reckoned  with  5.12  per  cent, 
of  foreign  salt  ? 

64.  What  amount  of  potassium  carbonate  must  be  pre- 

cipitated with  tartaric  acid  in  order  to  yield  the 
tartar  for  the  furnishing  of  100  g  of  tartar  emetic? 

65.  How  much  pure  heavy  spar  must  be  heated  with 

carbon  in  order  to  obtain  as  much  barium  sulphide, 
as,  decomposed  with  HC1,  and  then  precipitated 
with  alkali  carbonate,  gives  just  as  much  barium 
carbonate  as  is  necessary  to  yield  20  g  of  anhydrous 
barium  acetate  ? 

66.  For  the  yielding  of  potassium  iodide,  heavy  spar  is 

converted  into  barium  sulphide,  the  sulphur  in  this 


CHEMICAL   PROBLEMS.  75 

is  precipitated  with  iodine,  and  the  obtained  barium 
iodide  with  potassium  sulphate.  What  is  the  con- 
sumption of  heavy  spar  and  potassium  sulphate,  if 
25  g  of  potassium  iodide  are  obtained  ?  How  much 
potassium  iodide  can  be  obtained  as  bye-product  by 
means  of  the  precipitated  barium  sulphide  in  a 
subsequent  similar  operation  ? 

67.  In  order  to  produce  chrome-alum,  sulphurous  acid 

can  be  conducted  into  acid  potassium  chromate 
saturated  with  sulphuric  acid.  What  is  the  neces- 
sary proportion  ?  (Or,  what  is  the  corresponding 
formula  ?) 

68.  For  the  yielding  of  ammonium  sesqui-carbonate,  a 

liquid  containing  10  per  cent,  of  ammonia  (NH3) 
will  be  saturated  with  muriatic  acid,  the  obtained 
sal-ammoniac  is  distilled  with  calcium  carbonate. 
The  question  becomes:  (i)  How  much  muriatic 
acid,  containing  24  per  cent,  of  acid  contents,  is 
needed  to  yield  100  Ibs.  of  ammonium  sesqui-car- 
bonate ?  (2)  What  is  the  formula  of  the  latter  pro- 
cess from  which  the  necessary  quantity  of  lime  can 
be  calculated  ?  It  is  known  that  ammonia  will  be 
liberated  by  the  distillation. 

69.  In  the  preparation  of  potassium  ferri-cyanide,  a  man- 

ganese di-oxide  was  employed,  for  the  evolution  of 
chlorine,  very  nearly  free  from  iron.  It  is  desired 
to  precipitate  the  manganous  chloride  with  potas- 
sium carbonate,  and  with  the  resulting  manganous 
hydrate  to  precipitate  the  ferrous  oxide  from  a  solu- 
tion of  manganous  chloride  containing  iron.  50  g  of 
ferro-cyanide  are  converted  into  ferri-cyanide ;  how 
much  ferrous  oxide  can  be  precipitated  with  the 
manganous  hydrate  obtained  in  this  way  ? 

70.  When  iodine  is  mixed  with  potassium  hydrate,  potas- 

sium iodate  and  iodide  result.  If  this  mixture  be 
ignited,  only  potassium  iodide  is  formed.  The 
question  then  is  :  (i)  What  are  the  formulae  for 


76  CHEMICAL   PROBLEMS. 

both  processes  ?  (2)  How  much  iodide  of  potassium 
may  be  obtained  from  100  g  of  iodine?  (3)  What 
bye-products  arise  and  how  much  ? 

71.  An  alum  shale  contains  6  per  cent,  of  iron  pyrites. 

It  is  found  after  the  trial  is  made,  that  to  10  per 
cent.,  the  whole  amount  of  sulphuric  acid  arising 
from  roasting  combines  with  alumina  and  the  potas- 
sium present,  while  that  ib  per  cent,  forms  basic 
ferric  sulphate.  The  question  is  :  How  much  potas- 
sium sulphate  must  be  added  to  the  lye  of  1000  Ibs. 
of  the  shale,  if  it  be  known  that  the  ashes  of  the 
same  contain  1.5  per  cent,  of  the  whole  weight  of 
the  crude  shale,  potassium  carbonate,  which  will  be 
converted  into  potassium  sulphate  by  the  sulphuric 
acid  already  formed  ? 

72.  What  profit  do  1000  cwt.  of  shale  afford,  by  the  fore- 

going relations  in  71,  if  20.06  per  cent,  is  deducted 
for  loss  ? 

73.  A   mother   liquor  contains   5   per  cent,   of  sodium 

iodide ;  what  per  cent,  of  iodine  is  obtained  from 
this  ?  What  per  cent,  of  black  oxide  of  manganese 
is  necessary,  if  the  same  contains  98  per  cent,  of 
manganese  peroxide,  and  how  much  muriatic  acid 
containing  15  per  cent,  of  the  acid  contents  is 
needed  ?  All  the  answers  should  be  in  per  cent,  of 
the  mother  liquor. 

74.  A  chrome-ore  contains  45  per  cent,  of  chromic  iron. 

What  per  cent,  of  the  same  may  be  obtained  in 
impure  mono-potassium  chromate,  if  this  be  mixed 
with  12  per  cent,  of  potassium  sulphate? 

75.  A  sample  of  mercury  contains  3  per  cent,  of  tin  and 

5  per  cent,  of  lead.  10  Kg  of  mercurous  nitrate  are 
to  be  obtained.  What  quantity  of  mercury  and  how 
much  30  per  cent,  nitric  acid  are  to  be  used,  and  by 
how  much  sulphuric  acid  can  the  dissolved  lead 
oxide  be  precipitated  ? 

76.  A  laundry  requires  daily   10  Kg  of  potash  with  a 


CHEMICAL   PROBLEMS.  77 

content  of  5  per  cent  water  and  12  per  cent,  salts, 
at  $7.50  for  50  Kg.  Instead  of  the  same,  partially 
disintegrated  soda  with  2  per  cent,  foreign  salts,  at 
$3.75  for  50  Kg,  is  employed.  What  will  be  the 
difference  in  cost  for  ten  days  ? 

77.  How  much  sulphuric  acid,  with  87  per  cent,  water 

in  addition  to  the  hydrate,  is  necessary  in  order  to 
expel  all  the  carbonic  acid  and  muriatic  acid  from 
12  g  of  potash,  which  is  combined  in  the  following 
manner : — 

15  Mol.  K2O,CO2  +  4  Mol.  K2O,SO3  +  6  KG  + 
9.09  per  cent.  H2O  ? 

78.  What  is  the  percentage  composition  of  a  quantity  of 

potassium  chloride  and  sodium  chloride,  which  in- 
creases in  weight  by  heating  with  sulphuric  acid  to 
the  amount  of  19.2  per  cent.  ? 

79.  What  amount  of  potassium  di-chromate,  how  much 

alcohol  containing  85  per  cent,  by  weight,  and  how 
much  sulphuric  acid  with  5  per  cent,  of  surplus 
H2O  are  necessary  to  yield  5  Ibs.  of  chromium 
potassium  alum  ? 

80.  How  much  potassium  permanganate  is  contained  in  a 

liter  of  a  solution  of  which  55  cu  cm  are  needed  to 
oxydize  o.i  g  of  oxalic  acid  ? 

8 1.  What  is  the  atomic  weight  of  a  metal  of  which — 

a.  56  g  with  98  g  of  sulphuric  acid, 

b.  7  g      "      12.25  g 

c.  5-o  g  '      3-2581  gHCl, 
form  a  neutral  salt  after  oxydation  ? 

82.  What  is  the  atomic  weight  of  a  metal  of  which — 

a.  1 08  g  dissolve  if  it  be  precipitated  with  63.4  g 

of  copper, 

b.  54  g  dissolve  if  it  be  precipitated  with  31.7  g 

of  copper, 

c.  5  g  dissolve  if  it  be  precipitated  with  2.9352  g 

of  copper  ? 


78  CHEMICAL   PROBLEMS. 

83.  The  analysis  of  a  substance  which  is  known  to  be  a 

chemical  compound  gave — 

lime 30-434 

magnesia 21.740 

carbonic  acid 47.826 

100.000 

What  is  the  formula  of  the  substance  ? 

84.  The  atomic  weight  of  fluorine  is  to  be  found,  when 

it  is  known  that  100  parts  of  calcium  fluoride  treated 
with  sulphuric  acid  gave  174.4  parts  sulphate  of  lime, 
and  that  the  calcium  fluoride  is  analogously  con- 
stituted to  the  calcium  fluoride. 

85.  A  compound  consists   of  ferric  and  ferrous  oxide. 

5.256  g  of  it  become  converted  into  oxide  by  dis- 
solving in  nitric  acid  and  then  precipitating  with 
ammonia;  5.478  g  of  ferric  oxide  are  obtained. 
What  is  the  percentage  composition  of  the  ore  ? 

86.  A  ferrous-ferric  oxide  is  reduced  by  hydrogen.    The 

following  is  known  : — 

the  quantity  of  water  1.599  g>  ancl 

that  of  the  substance  5.256  g; 

Or:— 
the  quantity  of  the  water  and  obtained  iron  3.8346  g  ; 

Or:— 

the  quantity  of  the  substance  and  the  obtained  iron. 
The  composition  of  the  substance  is  required. 

87.  What  is  the  approximate  formula  of  the  investigated 

compounds  in  numbers  85  and  86  ? 

88.  What  is  the   formula  of  a  material   of  which  the 

percentage  composition  is  as  follows : — 

alumina 15-57 

sulphuric  acid 35-82 

water 48.61 

100.00? 


CHEMICAL   PROBLEMS.  79 

89.  What  is  the  formula  for  the  mineral : — 

silicic  acid 64.70 

alumina 18.50 

potassium 1 6.80 

100.00? 

90.  In  order  to  determine  the  carbon  in  a  sample  of  iron, 

7.584  g  were  treated  in  a  flask  with  HC1,  and  the 
resulting  mixture  of  hydrogen  and  hydrocarbon 
conducted  through  a  heated  tube  containing  cupric 
oxide.  After  collecting  the  water  that  was  formed 
in  a  calcium  chloride  tube,  the  carbon  di-oxide  was 
absorbed  in  a  vessel  containing  potassium  hydrate. 
Before  the  determination  the  vessel  weighed  46.5  3 1  g, 
afterwards,  46.7069  g.  The  substance  remaining 
in  the  generating  flask  was  thrown  upon  a  filter,  and 
the  residual  carbon  repeatedly  washed  with  HC1. 
The  dried  filter  weighed  alone  0.5622  g,  and  with 
the  carbon  0*5841  g.  What  per  cent,  of  carbon 
does  the  iron  contain  ? 

91.  The  following  numbers  are  obtained  from  the  exami- 

nation of  a  combustible  substance:  10  g  weighed 
after  drying  5.844  g;  1.505  g  gave  0.1484  g  of 
ashes.  According  to  this  what  is  the  composition 
of  the  substance  ?  What  is  the  composition  of  the 
dry  substance  ? 

92.  By  a  sugar  examination  100  g  furnish  95.  g  of  sugar ; 
furthermore  a  cup  with  sugar  weighed  26.12  g,  the 
cup  alone  21.12  g;  the  cup  with  sugar  after  drying 
26.01  g;  further  2.113  g  of  sugar  furnished  0.028  g 
of  ashes.    What  is  the  composition  of  the  sugar  ? 

93.  By  the  examination  of  a  potassium  salt  5.23  g  were 
dried  and  its  weight  reduced  to  5.10  g.     Further- 
more 10  g  were  dissolved  to   1000  cu  cm,  and  from 
100  cu  cm  of  this  solution,  after  precipitation  with 
barium  chloride  (to  convert  the  alkali  sulphate  into 
chlorate)    the  potassium  was   precipitated  by  pla- 
tinic  chloride;  1.311  g  of  potassic  platinic  chloride 


80  CHEMICAL   PROBLEMS. 

were  obtained.  The  precipitate  formed  with  barium 
chloride  in  the  100  cu  cm  solution  weighed  0.917  g. 
Calculate  the  quantity  of  water  contained  in  the  salt, 
also  the  sulphates  of  sodium  and  potassium,  assum- 
ing that  only  the  alkalies  are  combined  with  sul- 
phuric acid  ? 

94.  By  the  examination  of  a  water  the  following  numbers 

were  obtained : — 

loco  cu  cm  gave  entire  residue 0.693  g, 

looo  cu  cm  gave  residue  after  ignition...  0.597  g, 

silicic  acid  found 0.0012  g, 

ferric  oxide  and  alumina 0.0021  g. 

The  lime  was  precipitated  by  oxalic  acid  from 
1000  cu  cm,  then  dissolved  to  1000  and  250  cu  cm 
of  this  were  titrated  with  a  solution  of  (KMnO4),  of 
which  i.o  cu  cm  corresponded  to  0.00286  g  of  lime. 
26.9  cu  cm  were  required. 

By  precipitating  the  magnesia  from  1000  cu  cm, 
0.01293  g  of  pyro-phosphate  of  magnesia  were  ob- 
tained. 

IOOO  cu  cm  gave  a  precipitate,  with  barium  chlo- 
ride, of  0.1536  g,  and  in  the  solution  filtered  off, 
0.0107  g  of  chlorides  were  found. 

IOOO  cu  cm  of  the  water  required  in  the  chlorine 
determination  1.833  cu  cm  X>  silver  solution  of  which 
I  cu  cm  is  equal  to  0.00355  g  of  chlorine.  How 
much  of  the  various  substances  does  the  water  con- 
tain in  100,000  parts  ? 

95.  Calculate  the  mineral  constituents  of  the  H2O  ac- 

cording to  the  results  which  were  obtained  in 
No.  94. 

The  chlorine  is  regarded  as  sodium  chloride.  If 
any  chlorides  still  remain,  these  are  considered  as 
combined  with  sulphuric  acid. 

The  sulphuric  acid  is  to  be  considered  combined 
with  lime,  the  rest  of  the  lime  and  magnesia  are 
combined  with  carbonic  acid. 


CHEMICAL   PROBLEMS.  81 

96.  The  examination  of  a  limestone  afforded  the  following 

numbers  for  the  dried  substance: — 

5.  g  left  behind  undissolved  0.1775  g.  100  cu  cm 
of  the  nitrate  solution  of  5  g  diluted  to  500  cu  cm 
gave  a  precipitate  with  ammonia  of  0.0075  g. 

1.45  g  of  limestone  furnished  in  the  carbonic  acid 
apparatus  0.597  g  °f  carbonic  acid. 

200  cu  cm  of  the  above  solution  yielded,  after 
separation  of  the  lime,  0.0299  g  of  magnesia  phos- 
phate. 200  cu  cm  of  the  same  solution  gave  with 
barium  chloride  a  precipitate  of  0.0322  g. 

0.06  g  of  potassium  chloride  were  obtained  from 
100  g  of  limestone. 

According  to  this  what  is  the  composition  of 
limestone  ? 

97.  Calculate  the  analytical  factors  for  the  following  pro- 
portions, i.  e.,  the  numbers  with  which  the  quantities 
found  must  be   multiplied   in   order  to   obtain  the 
corresponding  quantities  of  the  substance  sought. 

FOUND.  SOUGHT. 

a.  oxide  of  antimony,  antimony, 

b.  sulphide  of  arsenic,  arsenic  acid, 

c.  barium  sulphate,  barium, 

d.  barium  sulphate,  sulphuric  acid, 

e.  barium  carbonate,  barium, 

f.  lead  oxide,  lead, 

g.  plumbic  oxide  sulphate,  lead, 

h.  sulphide  of  lead,  lead  oxide, 

i.  calcium  carbonate,  calcium. 

98.  Also  the  following : — 

FOUND.  SOUGHT. 

a.  ferric  oxide,  iron, 

b.  ferric  oxide,  ferrous  oxide, 

c.  calcium  carbonate,  carbonic  acid, 

d.  cupric  oxide,  copper, 

e.  pyro-phosphate  of  magnesia,  magnesia, 

f.  pyro-phosphate  of  magnesia,  phosphoric  acid, 

g.  barium  sulphate,  sulphur, 
h.  water,  hydrogen, 
i.  zinc  oxide,  zinc, 

k.  tin  oxide,  tin. 


82  CHEMICAL    PROBLEMS. 

99.  How  many  cu  cm  of  oxygen,  reckoned  with  normal 
pressure  and  20°  C.  are  necessary  to  furnish  the 
carbonic  acid  which  will  exactly  answer  for  the  pro- 
duction of  1000  Kg  of  a  white  lead  containing  5  per 
cent,  excess  of  water,  and  25  per  cent,  of  heavy  spar ; 
but  in  other  respects  corresponds  to  the  formula  3 
PbO,  H,0,  2C02? 

100.  What   increase    in   volume  does   water   sustain,   if 

500  times  its  volume  of  muriatic  acid  gas  be  dis- 
solved in  it,  when  the  spec.  grav.  is  increased  to 
1.21  (at  o°)  by  this  operation? 

101.  How  much  black  oxide  of  manganese,  with  15  per 
cent,  of  foreign  materials,  is  necessary  to  furnish 
the  chlorine  which  converts  I  Ib.  of  arsenious  acid 
(anhydride)  into  arsenic  acid  (anhydride),  if  only 
12)4  per   cent  of  the   chlorine   entered   into  the 
operation  ? 

What  is  the  volume  of  the  chlorine  (under  the 
normal  relations)  ? 


ANSWERS  TO  PROBLEMS, 


PART    FIRST. 


OXYGEN. 

1.  i6g. 

2.  a.  8  g.     b.  4  g.     c.  0.4  Kg.     d,  0.08  Kg.     e.  0.08  g. 
3-  MSg. 

4.  74.07  g. 

5.  a.  5  g.     b.  50  g.     c.  25  g. 

6.  a.  96  g.     £.  48  g.     c.  144  g.     </.  0.96.     e.  96  g. 

7.  (i)    200  g. 

(2)'  a.  100  g.     b.  50  g.     c.  5  Kg.     d.  l  Kg.     £.  I  g. 

(3)  18.52  g. 

(4)  925-93  g- 

(5)  a.  62y2  g.     b.  625  g.     c.  312.5  g. 

8.  a.  149  g.     b.  74.5.     c.  223.5  g.     d.   1.49  g.     *.   149  g- 
9-  3-9I8  g. 

10.  39. 1 8  per  cent. 

11.  a.  391.8  g.     3.  i  Kg  77  g,  (1.77  Kg). 

12.  a.  I  g.     b.  32  g,     c.  0.3912  g. 

13.  (10)  60.82  per  cent. 

(11)  a.  608.2  g.     b.   1.67  Kg. 

(12)  a.  1.5521  g.     b.  49.7  g.     c.  0.608  g. 

14.  0.  32  g.     b.  3.2  Kg.     c.  320  g.     </.  8  Kg.     e.  80  g. 
T5-  a-  73'56  ft>s.     £.  0.368  Hbs. 

16.  i6g. 

83 


84  ANSWERS   TO    PROBLEMS. 

17.  a.   18.4  Kg.     b.  0.184  K>s. 

1 8.  <z.  9.2  Kg.     £.   1.84  Kg.     <:.  5.33  g. 

19.  £.   i6g'.     <:.  0.16  g.     d.  3.2  Kg.     e.  4  g.    /.  64  Kg. 

20.  (16)  10.67  g- 

(17)  a.  12.26  Kg.     b.  0.1226  fibs. 

(18)  a.  6.1  Kg.     b.  1.226  Kg.     c.  3.55  g. 

21.  a.  50  per  cent,     b,  33%  per  cent.     c.  16%  per  cent. 

22.       x  l/2  or  y,. 

23.  98  g. 

24.  i6g.     151  g. 

25.  a.  49  Kg.     b.  7  g.     <:.  56.32  Kg.     </.  11.26  fts. 

26.  0.  75.5  Kg.     b.  10.8  g.     ^.  86.78  Kg.     d.  17.35  ft>s- 

27.  a.  216  g.     £.  432  g.     c.  324  g.     </.   108  g.     e.  54  g. 

28.  a.  13500  g.     b.  27  g.     c.  67.5  g.     d.  135  g.     <?.  19.3536  g. 
29-  X  I3-S- 

30.  a.  245  g.     £.  122.5  g-     c-  367-5  Kg-     <£  2-45  g-     e.  0.245  Kg. 

31.  a.  2.55  g.     £.  2552  g.     c.   log.     </.   I  g.     <?.  3.659  g. 

32.  130.5  Kg. 

33.  a.  32.6  g.     b.  1.305  g.     c.  26.1  Kg. 

34.  a.  87  Kg.    b.  loo  Kg.    ^.  i  g.    d.  50  Kg.    e.  10  Kg.   /  29  g. 

35.  a.  87  g.     b.  43.5  g.     <:.  21.75  Kg-     d-  2.I7S  ft8- 

36.  a.  50.025  Kg.   £.  10  Kg.   c.  29  g.   </.  loo  g.   e.  I  g.  /  543-75  g- 
37-  (35)  «•  98  g-     *.  49  g-     '•  24-5  Kg.     aT.  0.245  K>s. 

(36)  ^.  56.3  Kg.    b.  II. 27  Kg.    <:.  32.64  g.    aT.   112.7  g.    e.  1.127  g. 

/.  612.5  g- 

38.  a.  87  g,  and  98  g.  £.  108.75  R>s->  and  I22-5  fbs.  r.  543.75 
g,  and  612.5  g-  d-  5-437  Kg,  and  6.125  Kg.  e.  7.795  g, 
and  8.78  g. 

39-  19.3536  g. 

40.  29.0304  Kg. 

41.  a.  13.665  cu  m.  b.  2.733  cu  m>  c-  o.ooi  cu  m. 

42.  7-795  g.  and  8.78  g. 


ANSWERS   TO    PROBLEMS.  85 


HYDROGEN. 

I. 

a.  2  Kg.     b.  1  6  Kg. 

H. 

0. 

2. 

a.  I  Kg, 

8  Kg. 

b-  4g, 

32  g- 

c-  3  g» 

24  g- 

d.  i  Kg, 

8  Kg. 

'•  9  Kg, 

72  Kg. 

/.    0.02  g, 

0.16  g. 

X-    2g, 

A.  i  Kg, 

i6g. 
8  Kg. 

H. 

0. 

3- 

a.   Vg  Kg  (ii  I.I  1  1  g), 

%  Kg. 

b-  5-55  g» 

44-44  g- 

<:.  m^g, 

888  %  g. 

d.  27.78  g, 

222.22  g. 

4- 

«•  2  g-       *•  3/4  g-       f-   "-I"  g- 

d.   i.i  g.       e.  33.33  g. 

/.   in.  ii  g. 

5- 

a.   1  6  g.       £.  26%  g.      r.  88.89  g. 

</.   8.9  g.      e.  266.67  g. 

/.   888.89  g. 

6. 



7- 

a,  _*_  9.     b.  X  Y9- 

. 
9- 

a.  i  Kg.     b.  2.04  g. 

10. 

a.  No.     The  one  is  conditioned  by 

the  other,     b.  35.5  g  Z  in 

excess. 

ii. 

142.8  g  (/7  Kg). 

12. 

0.26  g. 

13- 

a.  ij-5  g-     b.  Q.i8  g.     c,  6.66  Kg.     i 

/.  0.8  Kg. 

14. 

a.  i  1.     b.  loo  1.     c.  1240  1. 

15- 

1860!. 

1  6. 

i.86ol. 

17- 

1500  cu  cm  CH4.     0.8064  H2O. 

18. 

98  Kg,  H2S04.     65.2  Kg,  Zn. 

19. 

81.7  g,  H2S04.     54.3  g,  Zn. 

H2S04. 

Zn. 

20. 

a.  4-39°  g» 

2.921  g. 

b-  439-0  g, 
r.  5.44  Kg, 

292.1  g. 
3.62  Kg. 

86 


ANSWERS   TO    PROBLEMS. 


21. 

22. 

23- 


24. 
25- 


a.  27  g.     b.  0.81  Kg. 
a.  24  g.     b.  0.72  Kg. 

H2SO4. 

a.  98  Kg, 

b.  4900  g, 
^.  4.3904  g, 


c.  40.5  g.     ^/.  90  g.     e.  80.64  g. 
c.  36  g.     </.  80  g.     ,?.  7i.68g. 

Zn. 

65.2  Kg. 
3260  g. 
2.921  g. 
2  Kg  921  g. 


d.  4  Kg  390.4  g, 
a.  0.8064  g.     b.  0.08064  1.     c.  80.64  Kg. 

a.  43904  g,  and  2.921  g.     b.  0.439  Kg,  and  0.292  Kg.     c.  439 
Kg,  and  292  Kg. 


CHLORINE. 

I. 

a.  71  Kg.     £.71  Ibs.     c.  0.71  g. 

2. 

«•  35-5  g-     b.  3  Kg  550  g.     c.  3.55  g. 

3- 

«.   71  g.     b.  710  g.     r.  81.608  Ibs.     </. 

16.322  g. 

4- 

a.  25.66  cu  dm.     £.   15.29  cu  dm. 

5- 

a.   146  Ibs.     b.  73  g.     r.   167.82  g.     d. 

i  Kg  678.16  g. 

6. 

a.  87  g.     b.  0.870  Kg.     <r.  297.94  g. 
/.  i  Kg. 

d.  5.959  Ibs.     <?.   10  g. 

7- 

MnO2. 
a.  87  g, 
b.  43.5  Ibs., 
c.  8.7  g, 
d.  50  Kg, 

£-.    IOO  g, 

/  59-59  g> 

HC1. 
I46g. 
73  Ibs. 
14.6  g. 
83.91  Kg. 
167.82  g. 

IOO  g. 

8. 

Mn02. 
a.  500  g, 
<*•  595-9  g, 
c-  3.897  Kg, 

HC1. 

839.1  g- 
1000  g. 

6.54  Kg. 

9- 

H2SO4.                               Nad. 
a.   196  g,                        117  g, 
b.   19.6  Ibs.,                   11.7  Ibs., 
c.  276.0  g,                     164.8  g, 

MnO2. 
87  g- 

8.7  Ibs. 

122.5  g- 

10. 

H2S04.                               Nad. 
a.  878  I  g,                      524.15  g, 
b.  8  781  Kg,                 5.241  Kg, 

MnO2. 
3  898  Kg.' 

n. 

63.616  g. 

12. 

I  :  1.0063616. 

ANSWERS   TO    PROBLEMS. 


87 


13.  198.72  cu  cm. 

14.  a.  73  Ibs.      6.  36.5  Kg.      c.  7.3  g.     d.  62.4  Ibs.      e.  623.93  g. 
/.  0.624  g- 

15.  a.  73  Ibs.      b.  36.5  g.      c.  3.65  g.      d.  0.745  g.      e.  186.22  g. 
/  74-49  Kg. 

16.  (14)  #.   142  Ibs.     b.  71  Kg.    c.   14.2  g.     </.   121.36  Ibs.    e.  1213.6  g. 

/   1-2136  g. 

(15)  a.   142  Ibs.      b.  71  g.      c.  7.1  g.      d.   1.44898  g.      e,  362.24  g. 
/.   144-898  Kg. 

17.  a.  117.  g.    £.  58.5  Ibs.   r.  .0.836  g.    d.  1 3 1. 326  Ibs.  ^.  H93.877g. 
/•  29.847  g. 

H2SO4.  NaCl. 

1 8.  a.  98  Ibs.,  117  Ibs. 
b-  49  g,                                                   58.5  g- 

c.  I  Kg  342.4  g, 

d.  134-24  g, 

19.  1.6352  g. 

20.  2  Kg  195.2  g,  acid.     2  Kg  620  g,  salt. 

H2S04. 

21.  a.  93.97  Ibs., 

b.  1879.4  g, 

c.  281.91  Kg, 

H2O. 

a.  1631^  fbs., 

b.  3266%  g, 
'•  490  Kg, 

22.  39.54  per  cent. 
23-  7.56  per  cent. 
24.  1 76.45  cu  cm. 

NITROGEN. 

1.  14.43. 

2.  I293  g. 

3.  a.  0.001293.     b-  773- 

4.  «.  0.90446.     b.   1.03079. 

5.  14.42  times. 

6.  76.7  N.     23.3  O. 

7.  1.2656  cu  m.     295.3  g  P- 


Kg  602.7  g- 
160.27  g. 


NaCl. 

112.19  Ibs. 
2243.8  g. 
336.57  Kg. 
Na2S04. 

136.16  Ibs. 

2723-3  g- 
408.48  Kg. 


88 


ANSWERS   TO    PROBLEMS. 


NITRIC  ACID. 


8. 

126  g. 

9- 

a.  63  Ibs.       b.  12.6  g.       c.  741.2  g. 
260  g.     /  6.3  g. 

d.  6.3126  g.       e.   I  Kg 

10. 

14.28  per  cent. 

ii. 

iif  or  Yv  also:  «•  54  ft*,    b.  10.8  g. 
*.  i  Kg  80  g.    /.  5.4  g. 

c-  635-3  g-    d.  5.4108  g. 

12. 

a.  27  Ibs.       b.  5.4  g.       f.  3I7.65  g- 

d.  2.7054  g.      e.  540  g. 

/•  2-7  g- 

!3- 

2000  g.     740  g,  H2O. 

14. 

a.  98  Kg.      b.  49  ibs.      ^.  4.9  g.      d. 
/  6.92  g. 

1  1.529  g.      *.  576.47  g- 

.  Na2NO3. 

H2S04. 

IS- 

a.  170  g, 
b.  85  Ibs., 

'•  34  g, 
d.  8.517  g, 

98  g- 
49  Ibs. 
19.6  g. 
4.9098  g. 

<?.  134-92  g, 
/  148.41  ibs., 

77-77  g- 
85.55  Ibs. 

g.  1349.20  g, 

777-77  g- 

h.  944.44  g, 

544.44  g. 

Saltpeter.                                Acid. 

H2O. 

16. 

a.  425  ibs.,                 245  ibs., 

b.   1700  g,                        980  g, 

135  ft*. 
540  g. 

17- 

a.  60  ibs.     b.  30  g.     c.  0.139  ft*5-     ^- 

0-394  g-     e.  y^  g. 

18. 

a.  76  ibs.    3.  38  g.    c.  0.176  Ibs.    ^/. 

o-5  g.     '.  itfs  8- 

Oxide. 

Acid. 

19. 

a.  7.5  ft*., 
£.  0.2083  Kg, 
r.  0.52  g, 

9.5  Ibs. 
0.264  Kg. 
0.66  g. 

20. 

a.  108  g.     3.  27  g.     r.   1.895  g. 

21. 

N  =  82.353.     H  =  17.647. 

22. 

NH3,  31.8.         HC1,  68.2. 

23- 

0.7616  g. 

24. 

0.5893.         0.0007616. 

25- 

1904.  g.     In  ratio  I  :  1.38. 

26. 

a.  17  g.     b.  170  Ibs.     c.  158.878  g.     i 

*  317.757  g- 

ANSWERS   TO    PROBLEMS.  89 

27-  34  g- 

28.  a.   17  g.     b.  4%  fibs,     c,  0.60714  Ibs.     d.  607.14  g. 

29-  a-  55-5°  g-     b.  13.875  fibs,    c.  1.98  fibs.    ^.  1982.14  g. 

30.  a.  56  g.     b.  28  fibs.     ^.  0.523  fibs.     </.  523.36  g. 

31.  a.  107  g.      £.  13.375  ft>s.      ^.   1.9107  Kg.      </.  i  ib.      <f.   i  Kg. 
/  nog. 

32.  a,  107  Ibs.       b.  53.5  g.       c.  nog.       d.  I  Kg.       e.  3.147  Ibs. 
/  3  H7  g- 

33-  a.  56  g.    b,  28  Ibs.    <:.  14  g.   </.  i  g.   <r.   1000  fibs.  /  164.7  Ibs. 

34.  a.  3147.06  g,  and  1647.06  g.     b.  31.5  fibs.,  and  16.5  fibs. 

35.  16.777  Kg.         8.781  Kg. 

SULPHUR. 

1.  192  Ibs.       648  fibs. 

2.  a.  228.57  g,  and  771.428  g.       b.  228.57  R>s.,  and  771.428  R)s. 
c.  8  g,  and  27  g.     d.   114.28  g,  and  385.714  g. 

3.  a.  840  g.     b.  420  g.     <:.  4.375  fibs.     </.  35  Kg.     <?.   iiolbs. 
4-  64  g. 

5.  a.  2  g.     3.  40  fibs.     c.  100  Kg.     </.  2  Kg.     <?.  10  g. 

6.  32.     i  liter  weighs  2.8672  g,  which  contains  1.4336  g  O. 

7.  a.  0.6975  !•     £•  6-975  !• 

8.  <z.  64  g.     /£.  6.4  fibs.     c.  i  Kg  600  g.     d.  1009.46  g. 

9.  a.  159.4  g.     b.  15.94  Ibs.     c.  3-Kg985g-     d-  2514.2  g. 

10.  a.   128  g.     3.  64  Ibs. 

11.  a.  128  fibs.     b.  65.3  fibs.    c.  48  g.     d.  320  g. 

12.  a.  44  fibs.     b.  22.45  ^s-     c-  l&-5  g-     ^  nog- 

13.  a:.  196  fibs.     b.  98  g. 

14.  a.  3.091  g.     b.   15.45  g.     <:.  31  fibs.     d.  3091.48  g. 

15.  a.  63.4  fibs.     b.  i  g.     c.  5  g.     a'.   10.027  ft>s.     ^.   I  Kg. 

16.  a.  12  g.     £.  6  fibs.     c.  i  fib.    </.  nog. 

17.  42.26  g. 

18.  <z.  22  g.     b.  i  Kg  loo  g.     c.  8.594  fibs.     d.  6.875  g- 

19.  «.  98.     b,  80.     ^.  16. 

20.  a.  49  fibs.     £.  7.656  fibs.     c.  7  Kg  656  g.     d.  306.25  g. 
G 


90  ANSWERS   TO    PROBLEMS. 

21.  a.  Half.         b.  The  whole. 

22.  (l)    a.  196  Ibs.     b.  98  g.     r.  30.625  Ibs.     </.  61.25  g- 
(2)    a.  98  fbs.     £.  49  g.     c.  15,3125  Ibs.     d.  30.625  g. 

23.  ®.  3  Kg  62.5  g,  and  990.625  g.     b.  306%  ft>s.,  arid  99  lt>s. 

24.  a.  i  Kg  531.25  g,  and  93.75  g.     b.  153^  ft>s.,  and  9^  R>s. 
25-  4390.4  g,  and  268.  g. 

26.  878.1  g,  and  284.032  g. 

27.  a.  80  fibs.     b.  40  g.     c.  i%  ft),     d.  1250  g. 

28.  a.  1 6  Ibs.     b.  8  g.     <r.  #  ft).     </.  250  g. 

H2S04.  H2O. 

29.  •  a.  98  Ibs.,  1 8  Ibs. 

t>-  49  g>  9  g. 

c.  765.625  g,  140.625  g. 

d.  1531.25  g,  281.25  g. 

30.  (r)    #.  80  Ibs.       £.  2j£  Ibs.       r.  20  g.       of.  2.5  g.       ^.  250  Ibs. 

/.  2  Kg  500  g. 

(2)    a.  98  Ibs.     b.  3>/6  Ibs.     <-.  24.5  g.     d.  3.0625  g.     e.  306.25  Ibs. 
/  3  Kg  62.5  g. 

31.  a.  X  2^.     b.  X  i#. 

32.  c.  2  Kg  500  g.     ^.  3.0625  Kg.     c.  3.4028  Kg. 

33.  a.  64  g.     b.  1 6  Ibs.     c.  800  g.     d.  4  Ibs.     <?.  9.068  g. 

34.  a.  64  g,  &  18  g.        b.  4.5714  Ibs.,  &  1.2857  ft>s-        f-  4  ft)'s.,  & 
1.125  lbs-     ^-  653-°6  g>  &  183.67  g.     e.  9.6  Kg,  &  2.7  Kg. 

35.  a.  16  g.     b.  1. 14287  Ibs.     c.  lib.     </.   163.27  g.     e.  2.4  Kg. 

36.  5  cu  m,  O.  35-84  Kg,  anhydride.  43-9O4  Kg,  hydrate. 
8.064  1,  H2O. 

37-  47-936  Kg. 

a.  b. 

38.  98  Kg,  hydrate.  49  cwt.,  hydrate. 

107  Kg,  H2O  and  acid.  53.5  cwt.,  H2O  and  acid. 

48  Kg,  O.  24  cwt.,  O. 

208.7  Kg»  air.  104.35  cwt->  air- 

18  Kg,  H2O.  9  cwt.,  H2O. 

27  Kg,  H20.  13-5  cwt.,  H20. 

39.  a.  3.0625  Kg.  1.0463  cu  m,  O.    5  cu  m,  air. 
b.  306.25  Ibs.  52.316  cu  m,  O.  250.3  cu  m,  air. 


ANSWERS   TO   PROBLEMS.  91 

40.  34-88  cu  m,  O.     132.01  cu  m,  N,  separated.     H2O  =  28.12  Kg. 
Added  O  =  17.44  cu  m.     H2SO4.     £  J^;"  ||; 

41.  S  =  326.5  Kg.  O  =  489.7  Kg. 
Air  =  2102  Kg.                                   H2O  =  275.5  Kg- 

42.  94.H765  S.        5-88235  H. 

43.  a.  17.     b.  1.5232  g. 

SO2.  H2O. 

44.  a.  64  g,  18  g. 

*•  32  g,  9  g- 

c.  640  g,  1 80  g. 

d.  3.765  Ibs.,  I-°59  Ibs. 

45.  a.  2867.2  g,  SO2,  or  i  cu  m.     b.  0.8064  1,  H2O. 

46.  2150.4  g. 

47.  a.  34  g.     b.  I  Kg  700  g.     c.  8.5  g.    d.  0.386  Ibs.    e.  139.5  g« 
/  386.4  g. 

48.  a.  98  g.    b.  4  Kg  900  g.    c.  24.5  g.    </.  1.1136  Ibs.    f.  402.13  g. 
/  "13-7  g- 

49.  (i)    a,  88  Ibs.     £.  361.1  g.     r.  8.38886  Ibs.     <£  3942.4  g. 
(2)    a.  98  Ibs.     b.  402.08  g.     c.  9.34214  Ibs.     d.  4390.4  g. 

50.  a.  3.9424  g,  and  4.3866  g.     b.  985.6,  and  1097.6  g. 


PHOSPHORUS. 

1.  a.  62  g.     b,   15.5  Ibs.     c.  0.87324  Ibs.     d.  2.183  g- 

2.  a.  30  Ibs.     £.  0.42253  Ibs.     <r.  4.2253  g.     </.  422.53  g. 

P.  CO2. 

3-  «.  31  Ibs'.,  70  Ibs. 

b.  218.3  gf  492.96  g. 

c.  4.366  g,  9.859  g. 

d.  436-61  g,  985-9!  g- 

4.  295.8  g,  P.     265.6  cu  dm,  O.     1.2656  cu  m,  Air. 

5.  a.  34  g.     b.  17  g.     c.   1.37  g.     d.  2.74  g. 

6.  P.  91.18!.         H.  8.82. 

7.  a.  18  1.     b.  6  1. 

Lime.  P.  H20. 

8.  a.  84  g,  i24g,  27  g. 

b-  24-7  gl  36.47  g,  7.94  g. 

'•  3-7632  g,  5-555  g,  1.217  g- 


92 


ANSWERS   TO    PROBLEMS. 


Lime.                                      P. 

H20. 

9- 

a-  3-7632  g,              5-555  g» 

b.  940.8  g,                     1388.8  g, 

1.217  g. 
304-25  g- 

CARBON. 

CO. 

C02. 

i. 

28  g, 

44  g- 

CO. 

C0a. 

2. 

a.  2  Kg  333.33  g, 
b.  583-33  g, 
c.  233.33  Ibs., 
</.  0.28  g, 
e.  3.500  Kg, 
/  700  g, 

3  Kg  666.67  g. 
916.67  g. 
366.66  Ibs. 
0.44  g. 
5.500  Kg. 

IIOO  g. 

CO. 

C02. 

3- 

4- 

5- 

a-   I  Kg  333.33  g, 
b-  333-33  g» 
c.  133-33  lbs-> 
^.  0.16  g, 
e.  2  Kg, 
/.  400  g, 

2  Kg  666.67  g. 
666.67  Ibs. 
266.33  Kg. 
0.32  g. 
4  Kg. 
800  g. 

a.  1254.4  g.     b.  I97I-2  g- 

6. 

1860.1  cu  m,  O.     8857.1  cu  m,  Air. 

7- 

Half. 

8. 

a.  1860.1.     b.  1860.1. 

9- 

a.  44  g.    b.  440  g.    r.  II  Ibs.    d.  0.44  g.    *.  440  Kg.  /  100  Kg. 

10. 

«•  5-3  g-    ^  5-3  g- 

II. 

6-7454  g- 

12. 

a.  42.2  Ibs.     b.  843.83  g. 

13- 

38^1  Ibs.     8#x  Ibs.  lighter. 

14. 

20.625  g,  and  26.250  g. 

15- 

0.  28  g.     3.  28  g. 

1  6. 

a.  44  g.     £.  18  g,  and  54  g,  H2O. 

17- 

In  both  280  g,  or  223.2  cu  dm. 

18. 

a.  98  g.     b.  9.8  Ibs.     c.  2.94  g.     d. 

147  Kg.     <?.   107.8  Ibs. 

19. 

a.   107  g.     b.   10.7  Ibs.     c.  3.21  g. 

d.  160.5  Kg.     <?.  117.7  Ibs. 

20. 

a.  292  g.     b.  29.2  Ibs.     r.  8.76  g. 

d.  438  Kg.     e.  321.2  Ibs. 

ANSWERS   TO    PROBLEMS.  93 

21.  a.  12  g.     b.  9  Ibs.    c.  34.2857  g.    d.  0.42857  Ibs.    e.  0.2143  g« 

/•  537-6  g. 
22..  53.76  g. 

23.  a.  12  Ibs.       b.  6  g.       c.  96  g.       d.  537.6  g.        e.   I  Kg  200  g. 
/•  33-3  g- 

24.  a,   1000  Kg. 

25.  a.  365  g,  and  245  g.     b.  486.67  Kg,  and  326.67  Kg. 

26.  53-571  g,  CaC03.       130.333  g»  HC1.       6.428  g,  C. 

27.  4  Kg  480  g,  and  4  Kg  793.6  g. 

28.  17  Kg  920  g,  and  17  Kg  561.6  g. 

29.  a,  64  g,  nearly  12  g.       b.  32  Ibs.,  nearly  6  Ibs.       c.  4.21  Ibs., 
nearly  0.79  Ibs.       d.   16.842  g.,  nearly  3.158  g. 

30.  85.7  C.         14-3  H. 

31.  75.0  C.         25.0  H. 

32.  3  cu  m. 

33.  2  cu  dm. 

FLUORINE. 

1.  95  FL        5  H. 

2.  a.  40  g.     b.  20  Ibs.     c.  12.82  g.     d.  512.8  g. 

3.  a.   m^lbs.     b.  55.55  g.     c.  13.889  g.     d.   13-6  g. 

4.  a.  39  Ibs.,  and  49  Ibs.       b.  19.5  g,  and  24.5  g.      c.  1.95  g,  and 
2-45  g-       d-  58.5  g»  and  73-5  g-       e.  i   Kg  950  g,  and  2  Kg 
45°  g-       /  *  lb->  475  g>  and  2  Ibs.,  225  g. 

Fluorspar.  H2SO4.  H2O. 

5-  a>  39  g»  49  g,  5  g- 

b.  54.6  g,  68.6  g,  7  g. 

c.  7.8  g,  9.8  g,  I  g. 
d.  i-56g,  i-96g,  0.2  g. 
<?.  i  lb.,  280  g,  i  lb.,  480  g,  loo  g. 

6.  a.  136  g.     b.  68  Ibs.     c,  3.4  g.     d.   102  g. 

POTASSIUM. 

1.  a.  112  Ibs.     b.  56  g.  f.  8n.6g.  d.  162.32  Ibs. 

Unslaked  Lime.  Slaked  Lime.  Carbonate  of  Lime. 

2.  a.  56  Ibs.,         74  Ibs.,  100  Ibs. 
b-  28  g,          37  g,  50  g. 

c.  405.8  g,        536.2  g,  724.7  g. 

d.  8i.i61bs.,       107.2  Ibs.,  144.9  Ibs. 


94  ANSWERS   TO    PROBLEMS. 


Burnt  Lime. 

Carbonate. 

3- 

a.  56  lbs., 

b.  y2  ib., 
f.  12.5  g, 

d.  405.8  g, 

138  lbs. 
1.23  lbs. 
30.8  g. 
i  Kg. 

4- 

a.  i88g.    b.  376  lbs.    c.  2.725  lbs.    d.  2 

Kg  724.6  g.    e.  68.i2g. 

5- 

a.  6.48  g.    b.  107.97  g-    *•  I0-8  lbs-    <£  J 

Kg  79-7  g-    e.  26.99  g. 

6. 



7- 

a.   1231.7  g.     3.   14  cwt.,  78  lbs.     *:.   12 

cwt.,  31.7  lbs. 

8. 

a.  841.4  g.     £.  10  cwt.,  9.7  lbs.     c.  8  cwt.,  4*1.4  lbs. 

K3C03. 

CaNO3. 

9- 

a.  138  lbs., 
b.  68.31  lbs., 

164  lbs. 
81.17  lbs- 

d.  10  cwt.,  9.7  lbs., 
e.  683  cwt.,  1  6  lbs., 

IOOO  g. 

12  cwt. 
811  cwt,  88  lbs. 

10. 

428.6  cwt.,  CaCO3.         865.7  cwt.,  Saltpeter. 

Nitrate.                             Sulphate. 

Water. 

ii. 

a.  109.77  lbs.,              106.52  lbs., 
b-  33-66  g,                   32-64  g, 

4.240  lbs. 
1-3  g. 

12. 

533-  g>  Saltpeter.        517.2  g,  H2SO4. 

667.5  g,  Water. 

13- 

loo  KNO3         15.84  S.         17.82  C. 

14- 

74.82  KNO3.         11.858.         I3-33C. 

K2S.                               N. 

CO2. 

IS- 

a.  40.74  lbs.,                10.37  lbs., 
b.  2.037  g,                   0.518  g, 

48.89  lbs. 
2.44  g. 

N.                                    COa. 

Gas. 

1  6. 

a.  4.13  cu  m         -j-    12.40  cu  m 

16.53  cu  m. 

1.653  cu  dm. 

17.  a.  302.48  Kg.     b.  151.24^7. 

1 8.  28  N.         3.44  CO2. 

19.  a.  213  lbs.     b.  21.3  g.     c.  0.634  lbs.     d.  126.8  g. 

20.  a.  495  lbs.     b.  49.5  g.     c.  1.473  lbs-     ^  294.6  g. 

21.  a.  122.5  lbs-     b-  I2-25  g-     c-  0-364  g.     d.  72.9  g. 

22.  a.  75.25  parts,     b.  3.04  parts. 


ANSWERS   TO    PROBLEMS. 


K.                                       Mn02. 

HC1. 

23- 

a.  336  g,                        261  g, 

438  g. 

b.  2.743  Ibs.,               2.131  Ibs., 

3-575  Ibs, 

c.  2742.8  g,                 2130,6  g, 

3575-5  g- 

d.  54.8  Ibs.,                 42.6  Ibs. 

71.5  Ibs. 

24. 

a.  552  g.     b.  10.78  g.     <r.  8.62  Kg. 

d.  107.8  Ibs. 

S. 

CQ2. 

25- 

a.  888  g, 

176  g. 

&  17-34  g, 

3-44  g- 

c.  13.87  Kg, 

2.75  Kg, 

</.  1  73.44  Ibs, 

34.37  Ibs. 

26. 

a.  714  g.     £.  13-94  g-     £-  H.I5  Kg. 

d.  139.4  Ibs. 

27. 

80.4. 

28. 

a.  15  times,     b.  ^, 

29. 

From  16  S,  17^  K2CO8. 

SODIUM. 

I, 

Na. 

2. 

a.  Na2COs.    £.  K2CO8. 

3- 



Na.                           CO2- 

H30, 

4- 

<z.   58.49,                      41.51. 

b.  21.68,                  15.38, 

62.94. 

5- 

*.  318  Ibs.   b.  159  Ibs.    ^.  53  Kg.    d. 

746.5  Ibs.    e.  746,48  Kg, 

f.  52.25  cwt. 

CaCOs, 

C. 

6. 

a.  400  Ibs., 

156  Ibs. 

£.  200  Ibs., 

78  Ibs. 

ft  66^  Kg, 

26  Kg. 

af.  938.97  Ibs., 

366.2  Ibs, 

<?.  938.967  Kg, 

366.2  Kg. 

/.  65.73  cwt., 

25.63  cwt. 

Na2S04.                               CaCO,. 

c. 

7- 

a.  426  Ibs.,                   400  Ibs. 

156  Ibs. 

b.  1000  Kg,                938.97  Kg, 

366.2  Kg. 

c.  1339.62  Ibs.             1257.8  Ibs., 

490,56  Ibs. 

d.  669  Kg  8  1  1  g,         628  Kg  930  g, 

245  Kg  238  g. 

Crystallized  Na,SO4.                   CaCO8. 

C. 

8. 

a.  966  Ibs.,                     400  Ibs., 

156  Ibs. 

b.  161  cwt.,                 662^  cwt., 

26  cwt. 

c.  1125.87  cwt.,          466.2  cwt., 

1  8  1.  2  CWt. 

d.  122,59  Kg,              46.62  Kg, 

18.18  Kg. 

96 


ANSWERS   TO    PROBLEMS. 


Salt. 

HC1. 

9- 

<z.   351  Ibs., 
•b.  823.94  Kg, 
r.  1103.77  Ibs., 
d.  55I-89  Kg, 

219  lbs. 
514.08  Kg. 
688.7  lbs. 
344.34  Kg. 

10. 

II. 

12. 

110.37  Kg  salt;   92.45  Kg  H2SO4;    125.78  Kg,  CaCO3  ;  49-o6 
Kg,C;  68.87  Kg,  HC1;  85.54  Kg  basic,  CaSO4;  123.87  Kg  CO2. 

265.7  cu  cm. 

13- 

ii.  16  cu  dm. 

14. 

3X  to  i- 

IS- 

132.8  cu  dm. 

1  6. 

8:7. 

17- 

Na  16.23.         B(OH)3  36.64. 

H2O  47.12. 

18. 

Na  21.24.         B(OH)8  47-94- 

H2O  30.82. 

19. 

a.  122.8  cwt.,  borax;  34.07  cwt., 
b.     81.86  Kg,  borax;  22.71   Kg, 

Na2CO3. 
Na2CO3. 

20. 

a.   144.56  g.     b.  28.91  Ibs. 

21. 

NaCl.      a.  60.68  Cl.;    39.32  Na 
c.   loo  Cl.  ;    64.79  Na- 

b.    loo  Na.  ;    154.35  Cl. 

AMMONIUM. 

I. 

2  :  4  :  2  or  i  :  2  :  I.         200  :  34 

:  2  or  loo  :  17  :  i. 

2. 

a.  123.36  cwt.  ;  109.34  cwt.     b.  98.69  g;  87.47  g.     c.  12.34  Ibs.  ; 
10.93  lbs-     d>  4-934  g;  4-37  g. 

3- 

89.72  Ibs.  (NH4)2CO8;  160.74  lbs.  gypsum;  132.71  Na2SO4. 

4- 

loo  g,  (NHJ2C03  ;  61.86  HC1. 

5- 

110.3  and  341-1  lbs. 

6. 

2  per  cent. 

7- 

3.5  per  cent. 

BARIUM. 

BaS.                       Ba(OH)a 

BaNO..                    BaCla. 

i. 

a.  169  lbs.;              171  lbs., 
b.  84.5  g,  '              85.5  g, 
'•  72-53  g,              73-39  g, 
*•  725-32  g,            733-9  lbs., 

261  lbs.,               208  lbs. 
130.5  g,                104  g. 

112.02  g,                  89.27  g. 
1  1  20.2  g,                 892.7  g, 

ANSWERS   TO   PROBLEMS.  97 


2. 

C. 

a.  48  Ibs., 
J.  24  g, 
c.  20.61  g, 
</.  206  g, 

C03. 

1  12  Ibs. 

56  g- 
48.07  g. 
480  g. 

3- 

Heavy  Spar. 
a.    1  16.5  g, 

*•    53  g, 
<:.   280  g, 
d.  112.02  Ibs., 

C. 

24  g- 
10.9  g. 

57-7  g- 
23.08  Ibs. 

4- 

BaS04. 
«•    233  g, 
b.  116.5  rt>s-» 
c.   118.27  Ibs., 
</.  i  Kg  182.7  g, 

K8COa. 
138  Ibs. 
69  Ibs. 
70.05  Ibs. 
700.5  g. 

5- 

log. 

6. 

10.01  per  cent. 

7-    (5) 
(6) 

3-5i  g,  HC1. 
1.965  g,  HC1. 

8. 

5  per  cent. 

9- 

1.125  (NH4)20.        2.077  (NH4)2C03. 

10. 

Na3CO3. 
a.  29.0  g, 
b.  725.89  g, 
c.  I  Kg  451.8  g, 

BaCI2. 
21.  1  g. 
527.9  g- 

i  Kg  55.8  g. 

n. 

a.  1  1  .88  g,  salt.     b.  296.9  g,  salt.     c. 

593-91  g,  salt. 

CALCIUM. 

i. 

a.  56  Ibs.     b.  560  Kg.     c.  0.56  Ibs. 

d.  14  g. 

2. 

a.  74  Ibs.     b.  740  Kg.     <:.  0.74  Ibs. 

d.  18.5  g. 

3- 

a.  loo  Ibs.    3.  25  cwt.    c  .  250  Kg.    d. 

1  78.57  Ibs.   e.  17 

/  892.85  Ibs. 

4-  a.  n.i6cum.      b.  279  cu  m.      c.  55.8  cu  m.      d.  19.93  cu  m. 

e.  398.6  cu  m.     /  99.6  cu  m. 

5-  a.  1 8  Ibs.    b.  4^  cwt.    c.  45  Kg.    d.  32.14  Ibs.    e.  321.428  Kg. 
/.  160.7  Ibs. 

6.  a.  n.i6cum.     b.   19.94  cu  m.     c.  39.86  cu  m.     d.  558  cu  m. 


98  ANSWERS   TO    PROBLEMS. 


CaCla. 

Na3C03. 

7- 

a.  44.4  g, 

42-4  g- 

b.   i  Kg  no  Kg, 

i  Kg  60  g. 

c.   ill  g, 

1  06  g. 

d.  5.55  Ibs., 

5-3  Ibs. 

Lime.                          HaSO4. 

H20. 

8. 

a.   32.56,                      46.54, 

20.93. 

b.  41.17,                     58.83. 

9- 

a.  iS  Ibs.     b.  4.5  g.     c.  264.7  g- 

d.   13.23  g. 

10. 

a.  234  g.     b.  82.39  Ibs.     c.   I  Kg 

648  g. 

n. 

Cl. 

Limestone. 

12. 

<z.   142  Ibs., 

112  Ibs. 

*•  71  g, 

56  g- 

'•  13-97  g, 

1  1.  02  g. 

</.  55-9  Kg, 

44.1  Kg. 

13.  a.  44.61  1.     b.  8.787  cu  m.  c.   17.57  cu  m. 

HC1.  MnO*. 

14.  a.  292  Ibs.,  174  lbs\ 

b.  146  g,  87  g. 

c.  28.73  g>  17-12  g. 
</.  114.9  Kg,                                         68.5  Kg. 

15.  a.  858.93  Ibs.     b,  428.87  Ibs.     c.  2399.06  Ibs. 

16.  a.  24.66  Kg.     b.  165.5  Kg.     c.  84.97  Kg. 

17.  a.   1.4  g.     b.  2.775  g.     '•  3-4  g- 

18.  a.  18.666  per  cent.     b.  37  per  cent.     *.  45.33  per  cent. 

MAGNESIUM, 
i.  341.46  Kg. 

MgS.  K2CO,. 

3.  a.  492  g,  276  g. 

b.  123  Ibs.,  69  Ibs. 

c.  300  Ibs.,  168.3  Ibs. 

d.  3000  Kg,  1682.9  Kg. 

4.  a.  45  g.     b.  1 1. 25  Ibs.     c.  27.4  Ibs.     d.  274.4  Kg. 

5.  a.  41  Ibs.     b.  8.2  g.     c.  205  Ibs.     d.  2050  g. 

NH3.  MgO.  P2O5.  HaO. 

6.  a.  6.94,  16.33,  28.98,  47.75. 
b.  45.31  per  cent. 


ANSWERS   TO    PROBLEMS. 


99 


7.  a.  0.4  g.     b.  1.33  g.     c.  0.9  g. 

8.  a.  31.555  percent., 

b.  52.59  per  cent, 

c.  10.518  per  cent., 

d.  2.104  Per  cent, 


(2  NaO,PaOB.) 
59.1  per  cent 
98.5  per  cent. 
19.70  per  cent. 
3.94  per  cent. 


ALUMINUM. 

1.  (i)    a.  10.83  per  cent.  b.  36.13  per  cent. 

(2)  a.  1 1. 21  per  cent  b.  37.39  per  cent. 

(3)  a.  11.34  per  cent.  b.  37.80  per  cent. 

2.  (i)    a.  45.53  per  cent.  b.  54.47  per  cent. 

(2)  a.  47.10  per  cent.  b.  52.90  per  cent. 

(3)  47.64  per  cent.  37-8o  per  cent. 

Alum.  KaCO3. 

3.— 4.         a.  948.8  g,  414  g, 

b.  237.2  Ibs.,  103.5  lbs-» 

c.  92.29  Ibs.,  40.27  Ibs., 

d.  9.23  Kg,  403  Kg, 


11.34  per  cent. 

C0a. 
132  g- 
33  Ibs. 
12.84  Ibs. 
1.28  Kg. 


IRON. 

a.  72.41  per  cent.         b.  70.03  per  cent.         c.  59.89  per  cent. 
d.  48.27  per  cent. 

a'  3°4  g-     &•  7-6  £•     c-  l-9  Ibs.     d.  38  g. 

a.  56  g.     b.  0.5989  g.     c.  5.6  g.     d.  0.599  g- 

a.  0.718  g.     3.  3.59  g.     c.  5.384  Ibs.     oT.  28.72  g. 

(1)  a.  14.23;  £.   18.30;  ^.  38.64;  d.  29.49. 

(2)  #.  4.74;  b.  6.10;  <r.   12.88;  d.  9.83. 

<r.  69.5  Kg.     d.  231.67  Kg. 
<:.  3003.086  Kg.    d.  180.185  Ibs. 
Water. 

63  cwt. 
1050  Ibs. 
31-5  Kg. 
105  Kg. 

HaO. 
882  Ibs. 
1361.1  Kg. 


a.  4.74;  b.  6.10;  c.  12.88;  , 
a.  139  cwt.     b.  2316.67  Ibs. 
a.  1946  Ibs.     b.  300.31  cwt. 
Oxygen. 

a.  III6.I  cu  m, 

b.  186.0  cu  m, 

c.  ii. 16  cu  m, 

d.  37.20  cu  m, 

O. 

a.  156.25  cu  m, 
c.  482.25  cu  m, 


100 


ANSWERS   TO    PROBLEMS. 


10. 

a.  1  6  cwt.     <5.  266.67  Ibs.     r.  8  Kg. 

d.  26.67  Kg. 

II. 

a.  278  Ibs.     b.  139  g.     c.   1390  g.     </. 

695  Ibs. 

12. 

X- 

'3- 

a.  315  parts.     3.   157.5  Parts- 

14. 

i6. 
17. 

K3S04. 
a.  87  g, 
*•  3-457  g, 
c.  0.173  lbs-» 

FeSOv 
200  g. 
7-952  g. 

0.397  Ibs. 
K3C03. 

138  g. 

65.4  Ibs. 
654  Kg, 

Fe. 
a.  28  g, 
£.   13.27  Ibs., 
c.  132.7  Kg, 

18. 

FeCya. 
a.  1  106  g, 
b.  55-3  lbs., 
c.  128.6  Ibs., 
d.  1286.05  Kg, 

FeaCl,. 
650  g 
32.5  Ibs. 
75-58  Ibs. 
755-81  Kg. 

19. 

FeCya. 
a.  162  g, 
b.  40.5  Ibs., 
c.  87.85  g, 
^.  486  Ibs., 

FeS04. 

152  g. 
38  Ibs. 

82.43  g- 
456  Ibs. 

20. 

FeCya. 
a.  972  g, 
£•  243  g, 
c.   1  1  3.02  g, 
d.  1130.23  Ibs., 

Fea03. 
i6og. 
40  g. 
1  8.60  g. 
186.04  Ibs. 

21. 

FeCya. 
a.  553-2  Ibs., 
b.   128.65  Ibs., 
c.   1286.5  cwt-> 
d.  643.25  Kg, 

FeSO4. 
456  Ibs. 
106.05  Ibs. 
1060.46  cwt. 
530.23  Kg. 

22. 

a.  n.i6cudm.     3.  0.529  cu  dm.     c. 

66.11  cu  dm. 

23- 

a.  329  g.     b.  15.59  g.     <:.  19.49  Kg. 

24. 

a.  422  g.     b.  13.21  lb«.     r.  32.07  g. 

d.  I  Kg  283  g. 

ANSWERS   TO    PROBLEMS.. 


101 


2. 


MANGANESE. 

a.  88  g.     b.  4.4  g.     c.  2.2  Ibs.     d.  10.115  g. 

a,  67.6  per  cent.  b.  75.6  per  cent.  c.   90.7  per  cent. 

d.  37.8  per  cent. 


3- 

a-  "3-4  g'     «•  2.ii  g.     ^  I-4o  g- 

4- 

0.  68.  6  1  per  cent.         b.  34.30  per  cent.         f.  90.05  per 

d-  54'°3  Per  cent. 

CHROMIUM. 

- 

2. 

a.  200  g.     £.   131.58  g.     c.  131  Ibs. 

<*•  i  Kg  315  g. 

3- 

a.  294  g.     b.  193.42  g.     c.  1.93  Ibs. 

</.  i  Kg  934.2  g. 

Cr.-iron 

K2C03. 

4- 

a.  224  g, 

276  g. 

b.  loo  Ibs., 

123.2  Ibs. 

c.  76.2  Ibs., 

93.9  Ibs. 

</.  76  1.  90  g, 

938.8  g. 

K2Cr03.                           H2SO4. 

H2O. 

5- 

«•   294  g,                            392  g» 

36°g- 

b.  29.46  Ibs.                 39-28  Ibs., 

36.07  Ibs. 

c.  7-36  g»                   9-82  g, 

9.02  g. 

6. 

a.  388  g.     £.  76.58  g.     c.  255.26  g. 

d.  2.55  Ibs. 

K2CrO3.                    NH4C1. 

K2C03. 

7- 

a.  294  g,                     214  g, 

138  g. 

*>-  96-7l  g,                  70.39  g, 

45-39  g- 

c.  1.93  Ibs.,               1.41  Ibs., 

0.91  Ibs. 

K2Cr03. 

Pb,C4H604. 

8. 

«•   J94g» 

379  g. 

/J.  6.01  Ibs., 

1  1.  73  Ibs. 

c-  30  g> 

58-7  g- 

oT.  600.6  g, 

i  Kg  173.4  g. 

9- 

£.  8.84  per  cent.     3.  20.51  per  cent. 

10. 

a.  49  g.     <5.  24.5  Ibs.     c.  2.52  g.     d. 

6-31  g- 

ZINC. 

i. 

#.  67.01  per  cent.     b.  52  per  cent. 

2. 

a.  4.514  cu  cm.     <5.  0.564  cu  cm.     c. 

1.114  cu  cm- 

3- 

a.  32.5  g.     b.  8.125  Ibs.     c.  4.0625  g 

.     d.  8.024  g. 

102  ANSWERS  TO  PROBLEMS. 

4.  a.  143  g.     b.  35.75  Ibs.     c.  17.875  g.     d.  35.31  g. 

White  Vitriol.  CaCl. 

5.  a.   l6l  g,  III  g. 
b.   1 1.84  g,                                               8.16  g. 

c-  59 J  -91  g>  408.09  g. 

6.  a.  45.1  cu  cm.    b.  22.57  cu  cm.    <r.  0.825  cu  cm-    ^  41-22  cu  cm- 

7.  a.  30.35  per  cent.         b.  37.83  per  cent.         c.  63.52  per  cent. 
d.  75.20  per  cent.         ^.  58.39  per  cent. 


COPPER. 

1.  a.  187.4  g.     b.  93.7  Ibs.     c.  236.02  g.  </.  23.60  Ibs. 

2.  a.  241.4  g.     b.  120.7  Ibs.     £•  3°4-°3  g-     d.  30.40  Ibs. 

3.  Same  as  (2). 

CuSO4.  NaaC03. 

4.  a.  249.4  g,  286  g. 
b.  124.7  ««*»i  *43  Ibs. 
£•.  314.106  g,  360.20  g. 
d.  31.41  Ibs.,  36.02  Ibs. 

5.  a.  63  g.  b.  31.7  g.  <:.  loo  Ibs.  d.  50  g.  *.  10  Ibs. 

6.  fl.  31.7  Ibs.  £.  100  g.  c.  79.83  g.  d.  4  g. 

7.  (l)  a.  79.4  g.  b.  12.5237  g.  c.  6.26  Ibs.  d.  62.618  g. 
(2)  a.  142.8  g.  b.  22.5237  g.  c.  II. 26  Ibs.  d.  112.618  g. 

8.  a.  5.58  cu  dm.  b.  7.815  cu  dm.  c.  5  cu  dm. 

9.  a.  5.58  cu  dm.  b.  7.815  cu  dm. 

10.  (i)  a.  5.58  cu  dm.  b.  7.815  cu  dm. 
(2)  a.  31.7  g.  b.  44-4  g- 

11.  a.  159.4  Ibs.  b.  100.38  Ibs.  c.  1003.78  Kg.  d.  501.89  Ibs. 

12.  a.  318.8  Ibs.  b.  200.76  Ibs.  c.  2007.56  Kg.  d.  1003.78  Ibs. 

13.  23.56  per  cent. 

14.  a.  41. 76  Ibs.     b.  4.176  Kg.     c.  20.88  g.     d.  0.04176  g. 

15.  a.   183.11  Ibs.     b.   18.311  Kg.     c.  91.55  g.     d.  0.18311  g. 

16.  a.  235. 58  Ibs.     b.  ii. 78  Kg.     <:.  1177.9  Kg.     </.  235.58  cwt. 

17.  a.  8878  per  cent.         b.  79.85  per  cent.         c.  34.57  per  cent. 
d.  55.58  per  cent.         e.  57.43  per  cent.        f.  55.26  per  cent. 

18.  a.  691.4  g.     b.  1728.5  Ibs. 

19.  a.  14.36  cwt.     b.  143.6  Kg.     c.  2871.5  Ibs.     d.   143.6  cwt. 


ANSWERS   TO    PROBLEMS.  103 

20.  a.  71.61  per  cent.  b.   84.25  per  cent.          c.   80  per  cent. 
d.  90  per  cent. 

21.  a.  11.234  per  cent.     b.   14.0428  per  cent. 

22.  a.  672  g.     b.  6.72  g.     c.  90.81  g.     d.  268.8  g. 

MERCURY. 

Hg2Cla.  Hg. 

1.  a.  271  g,  200  g. 
&•  54-2  g,  40  g. 

c.  i  Kg  726.1  g,  i  Kg  273.9  g« 

d.  32.2  Ibs.,  23.8  Ibs. 

HgSO4.  Hg.  NaCl. 

2.  a.  296  g,  200  g,  Ii7g. 

b.  9.866  Ibs.,  6.666  Ibs.,  3.9  Ibs. 

c.  3.14225  Ibs.,  2.1231  Ibs.,  1. 2420  Ibs. 

d.  6.285  g>  4.2462  g,  2.484  g. 

HgSO4.  NaCl, 

3-  «•    H8  g,  58.5  g- 

b-  59-2  g,  23.4  g. 

c.  109.225  g,  43-I7g- 

4.  «.  100  g.     b.  2.952  Ibs.     c.  7  Kg  380  g.     d.  73.80  g. 

5-  a-  53I/41bs«     b.  24.16%  Ibs.     ^.  4833.33  Kg.     d.  4831^  cwt, 

6.  «.  6.77  per  cent.     b.  15.24  per  cent.     c.  19.65  per  cent. 

7.  a.  I2g.     3.  69.44  g. 

8.  ii  :  14. 

LEAD. 

!•  ^-33^-     &•  148.43  g-     '•     7-421  Ibs. 

2.  a.  207  g.  b,  92.82  g.  r.  4.6412  Ibs. 

3.  (i)  0.  n.i6cudm.  b.  5.0  cu  dm.  c.  125.1  cu  dm. 
(2)  a.  53.1  cu  dm.  b.  23.8  cu  dm.  c.  596.7  cu  dm. 

4.  «.  908  g.  b.  151.61  Ibs.  c.  50.52  g.  d.  3.8  Ibs. 

5.  a.  i6g.  £.  3.2  Ibs.  c.  2.335  g.  d-  n.68g. 

6.  a.  621  Ibs.     £.  80.13  lbs-     *"•  801.29  cwt.     d.  8  Kg  12.9  g. 

7.  <z.  22. 32  cum.    £.  2.88  cum.    c.  2880.17  cum.    d,  0.576  cu  m. 

8.  a.  446  Ibs.     b.   1.1765  Ibs.     c.  29.4  g.     d.  223  g. 

9.  


104  ANSWERS   TO    PROBLEMS. 


II. 

%. 

12. 

a.  772.3  Kg.     b.  77.23  Ibs. 

!3- 

a.  2007  Ibs.     b.  looo  Ibs. 

c.  100  Kg.     </.   1294.8  Kg. 

14. 

a.  86.61  per  cent.     b.  77.53 

per  cent.     c.  68.31  per  cent. 

15- 

a.  2.56  Ibs.     £.  2565  Ibs.     c.  256.57  Kg.     </.  10263  Kg. 

1  6. 

a.  66.6  per  cent.     b.  50  per 

cent.     c.  70  per  cent. 

SILVER. 

I. 

63-53  Per  cent- 

2. 

a.  216  g.     b.  0.6353  g-     c- 

3.176  g.     d.  63.53  g. 

3- 

23.66  g. 

Cu(N03)2. 

Ag30. 

4- 

211-53  g- 

787-03  g. 

5- 

a.   12.70.     <5.  63.51.     c.   10. 

6. 

«.  0.913  g.     £.  2.60  1  8  g.     f.  1.4635  g. 

7- 

a.  13.87  per  cent.     b.  8.654 

per  cent. 

8. 

a.  12.85  g-     ^-  4.98  g- 

9- 

80  per  cent. 

10. 

1076.22  Ibs. 

Au.                      Ag. 

CuSO4.                    Cu. 

ii. 

«•  3  g-             b.  1350  g 

.c.  2137.01  g.      d.  396.25  g. 

Au.                         Ag. 

CuSQ4.                      Cu. 

12. 

a.  0.3  g,               135  g, 

2I3-7°  g>            39-625  g. 

b.  0.4  g,              180  g, 

284-93  g,            52.83  g. 

c.  .06  g,              27  g, 

42.54  g,              7-925  g- 

13- 

a.  340  g.     b.  53.62  g.     <r.  26.81  g.     d.   13.40  g. 

14. 

a.  28.7  g.     b.   1.435  g-     c-  0.205  g-     ^-  4-1  g- 

TIN. 


Sn. 
a.  118  Ibs., 
b-  39-33  Kg, 
c.  2.622  g, 
d.  52.44  g, 
'.  52%  Ibs., 

HC1. 

73  Ibs 
24-33  Kg. 
1.622  g. 
32-44  g- 
32</9  Ibs. 

ANSWERS    TO    PROBLEMS. 


105 


a.  219  Ibs.     b.  73  Kg.     c.  4.87  g.     d.  97.33  g.     e.  97^  Ibs. 
a.  44.64  cu  dm.    b.  i.n6cudm.   c.  2.232  cu  dm.   d.  1.891  cu  dm. 
Mn02.  HC1. 

a.  174  g,  292  g. 

b.  4-35  g,  7-3  g, 

c.  8.7  g,  14.6  g, 
d-  7-37  g,  12.37  g, 

a.   14124.2  Ibs.     b.   141242.2  cwt.     <:.  70621.4  Kg. 
a.  50  per  cent.     b.  2$  per  cent. 
20.878  per  cent. 

ANTIMONY. 

a.  23.62  per  cent.     b.  24.76  per  cent. 

a.  340  g.     b.  42.5  g.     r.  8.5  Ibs.     d.  0.8416  g. 

SbCls.  Na2C03.  NaCl.  CO2. 

«•  457  g,  3!8g,  351  g,  !32  g- 

b.  22.85  g,          15.9  g,  17.55  g,  6.60  g. 

c.  1.56  Ibs.,        1.09  Ibs.,  1. 20  Ibs.,  0.45  Ibs. 

HC1. 

1095  g- 
27.375  Ibs. 
2.71  g. 


SbS4Na3. 

a.  962  g, 

b.  24.05  Ibs., 

c.  2.38  g, 

d.  238.12  g, 

a.  321  g.     £.  8.025  Ibs.     c.  0.79  g. 
71.76  per  cent. 


27 1. 04  g. 
*  79-45  g- 


ARSENIC. 

S.  As. 

a.  64  g,  150  g. 

£.  32  Ibs.,  75  Ibs. 

c.  29.91  Ibs.,  70.09  Ibs. 

d.  299.06  g,  700.93  g. 

S.  As. 

a.  96  g,  150  g. 

b.  48  Ibs.,  75  Ibs. 
c-  l6  g.  25  g. 

d.  390-24  g,  609.76  g. 

a.  0.99  g.     b.  3.30  g.     <:.   i-98g.     </.  2.4235  g. 

a.  3.75  per  cent.  b.  0.052  per  cent.     ^.  0.649  Per  cent- 
H 


106  ANSWERS   TO    PROBLEMS. 

PLATINUM. 
!•  39-27  Per  cent. 

2.  a.  0.254  g.     b.  3.838  g. 

3.  a.  0.945  g.     b.  1.709  g. 
4-  13-59  Per  cent- 


PART  SECOND. 


APPROXIMATE   RATIOS. 

1.  2:3. 

2.  7  :  12. 

3.  9  :  10. 

4.  1:4. 

5.  9  :  22. 

6.  12  :  5  :  2. 

7-  13  :  7- 

8-  5:3. 

9-  3  =  2. 
10.  4:3:5- 

TEMPERATURE   AND    ATMOSPHERIC    PRESSURE. 

1.  0.29133  cu  m. 

2.  83663  cu  cm. 
3-  43I94l- 

4.  1068.4 1. 

5.  10.042  acid;   17.325  air.  ' 

6.  4-651  per  cent. 

7.  230.6  Kg. 

8.  214.22  cu  dm. 

MIXED    PROBLEMS. 

1.  360  days. 

2.  H2SO4  =  457  d;   Zn  =  480  days. 

3.  113.8  g,H2S04.     75.48  g,  Zn.     47.42  g,K2C03. 

4.  44.5  Kg,  marble.     47.61  Kg,  H2SO4. 

107 


108  ANSWERS   TO    PROBLEMS. 

5.  500  1,  H2O.     22  Kg,  400  g,  CaCO3.     21  Kg,  952  g,  H2SO4. 

6.  36-5  g- 

7.  2.1  mm. 

8.  a.  4  1,  H20.     b.  43.904  g,  H2S04.     c.  39.424  g,  FeS. 

9.  9.962  1,  H2O.    0.0983  Kg,  FeS.    0.1095  Kg>  H2SO4. 

10.  0.06896  per  cent. 

11.  0.0525  g. 

12.  O.OO297  g,  C. 

14.  18.25  per  cent. 

15.  21.368  per  cent. 

16.  a.  0.0065.     ^-  0.0107. 

17.  0.0136. 

*8'  93-3  per  cent. 

19.  a.  0.1346  per  cent.     b.  0.226  per  cent.     c.  0817  per  cent. 

20.  a.  0.2218  per  cent.     b.  0.2994  per  cent.     c.  0.2024  per  cent. 

21.  93. 1 6  per  cent. 

22.  For  carbonate  16.66.     For  phosphate  66.61. 

23.  10.08  per  cent. 
24-  35  Kg. 

25.  47.3  g,  K,  and  15.4  g,  Na. 

26.  27-73  Per  cent.,  K.     8.81  per  cent.,  Na. 

27.  20.36  per  cent,  K2CO3.     7.53  per  cent.,  Na2CO3. 

28.  K  5/7  of  Na. 

29.  ii  Kg  of  latter  less  than  5.3  Kg  of  former. 

30.  15.15  cts.  +. 

31.  152.9  cu  dm,  Cu.     16719.4  Kg,  Vitriol  sol. 

32.  $16.00  -f . 

33.  0.834  Ag  (or  83.4  per  cent.). 

34.  327.7  Ibs. 

35-  a-  33-396  Ibs.     b.  74.382  Ibs. 

36.  a.  55.407  Ibs.     b.   123.12  Ibs. 

37.  11.63  Kg. 


ANSWERS   TO    PROBLEMS.  109 

38.  50.8  g.  NaCl.     43.07  H2SO4. 

39.  12  per  cent. 

40.  42.97  Kg. 

41.  14.10  Ibs. 

42.  332.25  Ibs.,  saltpeter.     347.11  Ibs.,  H2SO4. 

43.  a,  213.33  Kg,  lime;  525.71  Kg,  KCO3.     b.  600.2  KNO3. 

44-  34-47  g,  Zn.     61.25  g-  H2SO4. 

45-  33-84  g,  Zn.     158.5  g,  HC1. 

46.  745-15  g>  vitriol.     90.59  g,  iron. 

47.  386.93  Kg,  Eng.  H2SO4.     709-409  Kg,  bye-product. 

48.  1592.8  Kg,  N  substance.     120.8  Kg,  Fe.     667.7  Kg,  potash. 
49-  18.53  g- 

50.  50.22  g,  H2SO4.     3.09  g,  C. 

51.  17.9  per  cent.,  dead  burnt.       a.  28.6  per  cent,  H2O.       6.26.4 
per  cent.,  H2O. 

52.  73.895 
11.812 

14-293 

100.000 

53.  1.294  Ibs.,  PbO.     0.252  Ibs.,  H2SO4.     0.258  Ibs.,  CaCO3. 

54.  (i)  a.   1.33  Ibs.,  Cu.     b.  1.17  Ibs.,  Fe.     c.  5.80  Ibs.,  vitriol. 
(2)  1.34  Ibs.,  Zn. 

55-  3-43  g,  BaS.     2.15  g,  Na2CO3.     2.81  g,  K2CO3. 

56.  77.28  g. 

57.  489.5  cwt. 

58.  6.93  Kg. 

59.  146.2  g. 

60.  47.1  g,  calomel. 

61-  325.9  g- 

62.  262  Kg. 

63.  582.7  Kg. 

64.  21.2  g. 

65-  18.27  g- 

66.  17.55  g,  BaS.     13.10  g,  K. 


110  ANSWERS   TO   PROBLEMS. 

67.  K2O,  2  CrO3  +  H2SO4  +  3  SO2  = 
K2S04  +  Cr2(S04)  +  H20. 

68.  (i)    386.6. 

(2)    3  (CaO,C02)  +  6  NH4C1  = 

3  CaCl2  +  2  (NH4)20,  3  CO2  +  2  NH,  +  H2O. 

69.  4.89  g. 

70.  (i)    I2l-f  6K20=rioKI  +  K20,I205. 

(2)  130.7  g. 

(3)  6.3  g,0. 

71.  27.0  Ibs. 

72.  200  cwt. 

73.  4.23  per  cent.,  I.     1.48  per  cent.,  MnO2.     16.43  Per  cent.,  HC1. 

74.  88.6  per  cent. 

75.  7.763  Kg,  Hg. 

76.  $6.00. 

77.  46.08  g. 

78.  52.767  NaCl.     47.233  KC1. 

79.  1.473  lbs-,  K  salts.     2.066  Ibs.,  H2SO4.     0.813  Ibs.,  alcohol. 

80.  9.12  dg. 

81.  a.  b.  c.  56. 

82.  a.  b.  c.  108. 

83.  CaO,  MgO,  2  CO2. 
84- 

85.  FeO 38.02 

Fe2O3 61.98 

100.00 

86.  

87.  4  FeO,  3  Fe203. 

88.  A12O3,  3  SO3  -f  18  H2O. 

89.  K20,  A1203,  6  Si02. 

90.  4.52  per  cent. 

91.  a.  Combustible  sub 52.68 

Ashes 5.76 

Water.... 41-56 

100.00 


ANSWERS   TO    PROBLEMS. 


Ill 


92.  Sugar 95-°° 

Water 2.20 

Ashes 1.32 

Foreign  organ,  sub , 1.48 

100.00 

93.  In  loo  parts  :—H2O  2.48.     K  25.26.     H2SO4  31.49. 
Or, 

H20 2.48 

K2S04 46.76 

Na2S04 17-75 

Foreign  sub 33-QI 

IOO.OO 

94.  100000  parts: — 

Min.  sub 59-7° 

Org.  sub 960 

69.30 

Or  from  this: — SiO2  0.12.  Fe2O3  -f  0.21.          CaO  30.77. 

Mg  .466.         H2SO4  5.27.         KC1  1.07.         Cl  .65. 

95.  i ooooo  parts: — 

SiO2 0.12 

Fe2O3  -f 0.21 

CaC03 48.26 

CaSO4 8.96 

MgS04 99 

NaCl  1.07 

59-71 

96.  In  loo  parts  : — 

CuCO, 93.57 

MgC03 1.13 

Fe203  + 75 

CaS04 94 

CaCl2 0.06 

Sand  and  Clay 3.55 

IOO.OO 

97.  Factors : — 

a.  0.83562.    b.  0.80488.    c.  0.65665.    d.  0.34335.    e.  0.77665. 
/  0.92825.    g.  0.68317.     h.  0.93305.     i.  0.56000. 

98.  Factors : — 

a.  0.70000.     b.  0.90000.    c.  0.44000.     d.  0.79849.    e.  0.36036. 
/.  0.63964.    g.  0.13734.    /i.o.iiiu.    i.  0.80260.    k.  0.78667. 

99.  43.3  cu  m. 

100.  0.50. 

101.  8.27  Ibs.,  MnO2.     902  1,  Cl. 


THIS  BOOK  IS  DUE  ON  THE  LAST  DATE 
STAMPED  BELOW 


AN  INITIAL  FINE  OF  25  CENTS 

WILL  BE  ASSESSED  FOR  FAILURE  TO  RETURN 
THIS  BOOK  ON  THE  DATE  DUE.  THE  PENALTY 
WILL  INCREASE  TO  SO  CENTS  ON  THE  FOURTH 
DAY  AND  TO  $1.OO  ON  THE  SEVENTH  DAY 
OVERDUE. 


3=e- 


1S38 


19JatT49. 


OCT  "8  1940 


8EP191941M 


NOV  24 1941 Y 


**<} 


24 


2    1948 


APR    29  ID40 


16849 


THE  UNIVERSITY  OF  CALIFORNIA  LIBRARY 


